Precious metal palladium. Palladium properties, production and application Where is palladium used?

Banking analysts write about the insufficient satisfaction of demand for palladium - but the valuable metal is needed by industry, medicine, and jewelry.

Meanwhile, according to scientists, almost a palladium shower falls on the surface of our planet every year. Well, maybe not a downpour, but a faithful seven kilograms arrive from space every year!

Where does this wealth come from?

We are the children of the stars...

...and in the literal sense and most of the body. Larger - because some of the chemical elements that make up both human and celestial bodies were formed outside the stars. Palladium is the “son” of two processes occurring in the Universe. Some of it is synthesized in reactions occurring in massive stars. Part of the palladium, as well as the rest, is formed during supernova explosions.

Metal ejected into interstellar space sooner or later becomes part of a gas and dust cloud, from the mass of which stars and planets condense. Colliding and collapsing, celestial bodies are crushed - these are the fragments that the Earth collects in its journey through the orbits of the galaxy. The indicated seven kilograms of palladium are contained in two thousand tons of meteorites that fall on our planet per year...

A considerable amount of palladium is concentrated in burnt-out nuclear fuel from nuclear power plants. For obvious reasons, it is impossible to use metal from uranium-plutonium slag in any way. So right away it’s impossible, but after 10-15 million years (quite a bit by the standards of the Universe) it’s possible!

Two centuries since the discovery of palladium

The honor of discovering palladium belongs to a not very diligent English doctor, who showed remarkable research insight and excellent commercial agility.

William Wollaston, at that time already a full member of the Royal Society of London for the Knowledge of Nature, in the last years of the 18th century started a profitable business in the production of platinum utensils. Experimenting with ore residue, Wollaston isolates new metals, one of which the scientist names “palladium”, and the second “rhodium”.

The name palladium is quite random. In the early 1800s, the Greek goddess Pallas Athena became a household name when a recently discovered asteroid was named after her. In 1803, two years after the significant event, Wollaston gives the “new silver” the fashionable name of a wise warrior.

Richard the Unbeliever

At the beginning of the 19th century, science served as entertainment for many enlightened people. Wollaston was not without a slight hoax. The announcement he gave read: a noble metal has been discovered, similar in appearance and properties to m. Available for purchase...

The ambitious Irish chemist Richard Chenevix, who had just received the highest award from the Royal Society, decided to turn his success into triumph, and publicly promised to bring the fraudster to clean water. According to Chenevix, the unknown charlatan simply used the little-known Musin-Pushkin method, which made it possible to fuse mercury with platinum.

Having bought the ingot that was being sold, Chenevix hastily conducted research, and soon reported at a meeting of the academic council that he was right. All that remains is to expose the falsifier!

And then an advertisement appears in the newspaper: someone promises to pay 20 pounds to anyone who can fuse platinum with mercury so that they get “new silver”...

With rage turning into frenzy, Chenevix begins experiments. Other London chemists are also working with him at the same time. Needless to say, none of them manages to synthesize palladium or isolate platinum and mercury from the ingot purchased by Chenevix.

A year after the start of the epic, Wollaston gives a detailed account of the discovery. Soon he is elected president of the Royal Society. Richard Chenevix has to leave his chemistry classes...

Mining and use of palladium

Today, geologists count three dozen minerals that include palladium. A considerable amount of metal is included in the native formations of gold, silver and platinum. Norilsk platinum contains almost half of palladium! Brazilian prospectors have found gold nuggets with a ten percent precious metal content.

Deposits of palladium ores, as a rule, coincide with deposits of other non-ferrous metals, including nickel, mercury, and copper. According to modern estimates, the most promising palladium reserves are concentrated in Norilsk.

Amazing properties of palladium made it indispensable in the chemical industry. Palladium's ability to absorb hydrogen in a volume almost a thousand times greater than the volume of the metal is amazing! The use of palladium catalysts in the technological cycle of margarine production made it possible to eliminate the previously inevitable contamination of the food product with nickel.

Hot palladium is easily permeable to hydrogen. A millimeter-thick metal plate installed as a membrane removes hydrogen from complex gas compositions and solutions that do not otherwise release hydrogen.

Palladium alloys do not oxidize even under an electric arc, which opened the way for them to the electrical industry. Titanium with a small addition of palladium exhibits increased resistance to various chemical loads. Medicine cannot do without palladium: the metal is used in dentistry, cardiology, and pharmaceuticals.

Palladium in jewelry

Palladium itself is very decorative and can compete in expressiveness with silver, and even more so with platinum. Alloys containing palladium are highly valued by jewelers.
The so-called “” is most often nothing more than a combination of gold and palladium. The soft, discreet shine of noble metal is the best frame for! An alloy of palladium with indium - depending on the concentration of the ingredients - can have a color from a characteristic golden to a pronounced lilac hue.

Wedding rings made from an alloy with a high palladium content (palladium hallmarks - 500, 850, ligature - silver) are visually indistinguishable from rhodium-plated gold rings. At the same time, the owner of the jewelry does not need to periodically renew the rhodium plating. And palladium is somewhat inferior in price to gold.

The addition of palladium to platinum gives the product greater expressiveness and increases the technological properties of the material.

Hello! Palladium is a precious metal that is valued in many industries and especially in jewelry. Unique physical and chemical properties, similarity to platinum - all this makes it so popular. And yet, few people know what this metal is needed for and where to find it.

The chemical element is a plastic mineral having a silvery-white color. It is classified as a type of precious metal of the platinum group.

Brief history of appearance

Pd was first discovered in the 19th century. The chemical element was discovered by chemist William Wollaston (Great Britain). During the experiments, the scientist extracted it from platinum ore.

The metal received its name in honor of the asteroid Pallas discovered a year before. He, in turn, was so named thanks to the goddess from Ancient Greece Pallas Athena and her wooden image, the Palladium, which fell from the sky according to legend.

What does palladium look like in nature?

Nuggets are not found in nature in their pure form. Metal particles are extracted along with other minerals. According to approximate data, there are approximately 30 elements that come into contact with palladium.

Externally, grains of the precious metal are very similar to platinum. In some deposits, these two elements are mined together (called palladium platinum) and then separated by chemical processing. Also, veins can intersect with gold, then a combination of two metals is observed (for example, palladium gold or porpecite from Brazil).

The process of formation in nature

The main source of appearance is space fragments of meteorites. A large content of precious metal crystals was found in iron and stone types of alien fragments.

Structure, chemical and physical properties

By its nature, the mineral compares favorably with other precious metals with its low density and chemical inertness. Thanks to the latter property, it does not interact with other elements and does not oxidize.

1. Exceptions are silicon, boron, sulfur, chromium, with which palladium forms chemical compounds.
2. Also, metal crystals dissolve in “regia vodka” (this is a mixture of two acids - sulfuric and nitric).

Expert opinion

Vsevolod Kozlovsky

6 years in jewelry making. Knows everything about samples and can identify a fake in 12 seconds

In appearance, the nuggets are similar to platinum and silver. The metal is very ductile, which is why it is actively used in jewelry. To improve strength and wear resistance, it is used in compounds with other metals.

Melting point is 1554 degrees Celsius.

How are palladium veins found?

Mineral inclusions are sought primarily in the locations of silver, copper and nickel ores. Occasionally there are small deposits with nuggets of pure metal.

Palladium satellites

In the bowels of the earth, palladium is found exclusively in the form of compounds with other minerals. Some of them have been little studied to this day and have no name. The most famous satellites of the precious metal are:

• braggite;
• palladite;
• potarit;
• stannopalladite.

It is also often extracted from gold and platinum veins.

Where does palladium occur in nature?

Under natural conditions of the earth's interior, the mineral is found in the form of compounds of different metals. Similar veins are found in Europe, the Russian Federation, and America.

Types of deposits

Pd is most difficult to detect in the form of nuggets. Much more often it is included in the composition with other minerals, and after extraction from the depths it is separated by chemical treatment.

Deposits are divided into 2 types:

1. Placers are nuggets that have accumulated over many years and are located predominantly in areas of ore deposits.
2. Indigenous - represented in the majority, contain compounds of palladium with other minerals.

Extraction methods

Work with palladium deposits is carried out in two forms:

1. closed (mine);
2. open (career).

In the first case, a system of underground tunnels - mines - is created for the extraction of precious metals. Small holes are created in the found ore layer, into which explosives are then placed. The soil loosened by the explosion is processed mechanically or manually to extract palladium particles. Once the initial refining is complete, the ore is transported to the surface and then transported to further processing.

In the second case, heavy earth-moving equipment and vehicles are used to transport the extracted ore. With its help, a soil quarry is developed, from which palladium is then extracted. It is then transported for processing to the appropriate enterprises.

Top countries by production

Few people know where palladium veins are located:

1. The leaders in production are Russia and South Africa. The first accounts for 41% of production, and the second - 39%.
2. They are followed by Canada (9%), USA (6%) and Zimbabwe (3%).
3. The remaining countries account for 2% of production.

World reserves of palladium

Data on the presence of palladium in the earth's interior vary. According to some sources, its quantity is 2-3 times higher than gold reserves. According to others, it is 20 times inferior to him.

According to rough estimates, the ore layer of the earth contains 0.0006-0.015 ppm - parts of the mineral per million parts of other elements.

Areas of application

The element widely uses:

1. Chemical industry. Pd is a popular catalyst in oil refining and fat refining. Palladium chloride is also involved in the search for trace amounts of carbon monoxide in the air or gas mixtures. In electrochemistry, the same compound is an activating substance in the galvanic metallization of dielectrics. Palladium membranes are needed for hydrogen purification.
2. Electrical engineering. The metal is important as a coating that is resistant to sulfides: the manufacture of high-precision voltagometers. Its physical characteristics have led to its use in the production of ceramic capacitors.
3. Jewelry making. Palladium is added to products to create white gold. Even a small metal content in the alloy changes the shade of the item from yellow to silver-white. Occasionally, the mineral is used in the manufacture of commemorative coins.
4. Medicine . Palladium is added to drugs intended to combat tumors and cancer therapy. Another area where metal is used is dentistry. Here, dentures are made on its basis. Alloys with the addition of palladium are used to create individual parts of pacemakers and medical instruments.

The richest deposits

Although large amounts of palladium are found in pieces of meteorites that fall to earth, the bulk of production comes from ore deposits. They provide about 98% of the world's metal reserves.

In the world

The Bushveld complex (South Africa) is the world's largest deposit where palladium is mined. Here, prospectors find up to 40% of the world's precious metal reserves.

In much smaller quantities it is also extracted into:

• Lac des Iles (Canada);
• Stillwater (USA);
• Great Dike (Zimbabwe).

In Russia

The copper-nickel deposits that are part of OJSC MMC Norilsk Nickel are the largest metal suppliers in Russia:

• Oktyabrskoe;
• Talnakhskoe;
• Norilsk-1.

Their total profit is more than 40% of the global one.

Advantages and disadvantages of metal

First of all, the demand for palladium is determined by its physical characteristics:

1. Compared to platinum, it has less weight, and therefore jewelry based on it, even large ones, are not heavy at all. Moreover, its strength is much higher than that of gold. This allows it to be used as a setting for large jewelry stones. Over time, such decorations do not darken and do not lose their attractiveness.
2. Another undeniable advantage of palladium is its incredible external similarity to platinum. Wherein . According to rough estimates, the cost of 1 gram of metal is 2-3 times lower than that of gold or platinum.

As part of the alloy, palladium is resistant to wear, deformation, and scratches. However, pure metal has exactly the opposite properties, and therefore is used in rare cases, for example, for making exclusive jewelry. Palladium-based wedding rings are especially in demand. It is often used instead of nickel, providing a similar effect without causing an allergic reaction.

Types of alloys and samples

Since palladium in its pure form is too soft, alloys based on it are used to make jewelry.

In Russia, two samples are legally approved - 500 and 850. Nickel, silver and copper are used as alloys. 950 standard is also popular abroad. In this case, 95% palladium accounts for 5% copper or ruthenium additives. Occasionally they are replaced with nickel to provide greater strength to the alloy.

Sample correspondence table

Palladium alloys approved in Russia are prescribed in GOST. The composition and amount of ligature in each of them can be tracked using the table presented here.

Where can you buy or sell

To purchase palladium jewelry, you should contact a jewelry store. Occasionally, world-famous designers include precious metal and products based on it in their collections. In these cases, the goods you like can be purchased through branded stores. When it comes to souvenir coins, it is recommended to purchase them through a bank to ensure that you receive the real thing.

In case of returning precious souvenirs, this can also be done through banking institutions. The main condition is the impeccable appearance of the coin and the safety of its certificate. Jewelry is much more readily bought from pawn shops. If they are damaged, the products are taken back at the price of scrap.

How much does 1 gram cost today?

Palladium | RUB | 1 Gram

The situation is similar when selling other goods containing palladium (knitting needles, radio components, coins, etc.). In addition, sometimes the cost is determined not by the weight of the scrap, but by the piece.

How to spot a fake

Distinguish palladium from other metals by eye.

If there is any doubt about the authenticity of the metal, it is recommended to show it to an independent jeweler appraiser. You can be sure that you are holding real jewelry in your hands if over time they have not lost their attractiveness and shine. If the jewelry begins to darken, this is definitely a fake.

Make sure that the jewelry is marked with an indication of the purity (500 or 850).

The silvery-white color of the metal goes better with diamonds, sapphires, amethysts, labradorite and aquamarines.

When choosing wedding rings, pay attention to the shape of the inner surface. For comfortable wearing, it should be slightly curved.

Palladium jewelry is subject to the same care and cleaning instructions as gold:

• protect from household chemicals;
• remove before water procedures;
• store in boxes;
• periodically clean from dirt and deposits.

What radio components contain

In radio engineering, palladium is often found in the following parts:

• connectors;
• capacitors;
• resistors.

First of all, it is important in the military and space industries. In civil engineering, palladium is used only in aviation.

How to distinguish palladium from platinum in radio components

At home, distinguishing two precious metals is difficult, but possible. The easiest way is to drop a small sample into a container of nitric acid. If the metal dissolves, you have palladium.

Another method involves using a touchstone, potassium iodide and aqua regia. A metal sample is passed along the edge of the stone until a scratch is formed. Then a mixture of potassium iodide and aqua regia is poured into it. If the scratch is painted red with a brown tint, we can say that the presented sample is palladium.

Ways to isolate metal

Options:

1. Electrolytic reaction. Refining involves the use of sulfuric acid, which will separate the palladium compounds, leaving the brass and copper elements intact. Aqua regia will help extract pure metal after the reaction is complete.
2. Ammonia solution and hydrochloric acid also help to isolate palladium. The color of the precious metal plays an important role in the refining process. For example, brown confirms the presence of palladium in the alloy.

Also watch the video below about what else you can get palladium from:

Palladium is one of the elements of the periodic table, part of the platinum group

The history of the discovery of palladium and its occurrence in nature, biological, chemical and physical properties of palladium, the use of palladium in the jewelry industry, investments in palladium, palladium production, facts about palladium

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Palladium - definition

Palladium is an extremely heavy and very refractory ductile and malleable metal that is very easily rolled into foil and drawn into thin wire. In terms of its density, which is 12 g/cm3, palladium is still closer to silver, whose density is 10.5 g/cm3, than to its related platinum (21 g/cm3). Naturally occurring palladium consists of six stable isotopes: 102Pd (1.00%), 104Pd (11%), 105Pd (22%), 106Pd (27%), 108Pd (26%), and 110Pd (11%). The longest-lived and artificial radioactive isotope is 107Pd with a half-life of more than seven million years. Many isotopes of palladium are formed in small quantities by the fission of uranium and plutonium nuclei. In modern nuclear reactors, 1 ton of nuclear fuel with a burnup rate of 3% contains about 1.5 kilograms of palladium.

Palladium is one of the elements of the periodic table of chemistry. elements named after Mendeleev. In the table, this element has serial number 46 and is located in the fifth period of elements.

Palladium is noble metal belonging to the platinum group. It itself has a white-silver color.

Palladium is the only chemical element with an extremely filled outer electron shell. There are 18 electrons in the outer orbit of the palladium atom.

Paladium is an element often used in the production of white gold or as the base of a palladium alloy. Even 1-2% palladium is enough to give gold a silvery-white hue. But most often 14k white gold contains 13% palladium. It is most suitable for setting diamonds.

Palladium is an element that can enhance the anti-corrosion properties of even such a metal, resistant to aggressive environments, as titanium. The addition of palladium of only 1% increases the resistance of titanium to sulfuric and hydrochloric acids.

Paladium is the material from which most medals awarded to outstanding scientists and athletes are made.

History of the discovery of palladium

Palladium was discovered by the English physician and chemist William Wollaston in 1803 while studying crude platinum brought from South America, in the part that is soluble in aqua regia. Having dissolved the ore, Wollaston neutralized the acid with a solution of NaOH, after which he precipitated platinum from the solution by the action of ammonium chloride NH4Cl (ammonium chloroplatinate precipitates). Then mercuric cyanide was added to the solution, which formed palladium cyanide. Pure palladium was isolated from cyanide by heating. Only a year later, Wollaston reported to the Royal Society that he had discovered palladium and another new noble metal, rhodium, in raw platinum. Wollaston derived the very name of the new element, palladium, from the name of the small planet Pallas, discovered shortly before (1801) by the German astronomer Olbers.

The forty-sixth element, due to a number of its remarkable physical and chemical properties, has found wide application in many areas of science and life. Thus, some types of laboratory glassware are made from palladium, as well as parts of equipment for separating hydrogen isotopes. Alloys of palladium with other metals find very valuable applications. For example, alloys of the forty-sixth element with silver are used in communication equipment (making contacts). Temperature regulators and thermocouples use alloys of palladium with gold, platinum and rhodium. Certain palladium alloys are used in jewelry, dental practice (dentures), and are even used to make parts for pacemakers.

When applied to porcelain, asbestos and other supports, palladium serves as a catalyst for a number of redox reactions, which is widely used in the synthesis of a number of organic compounds. Palladium catalyst is used to purify hydrogen from traces of oxygen, as well as oxygen from traces of hydrogen. Palladium chloride solution is an excellent indicator of the presence of carbon monoxide in the air. Palladium coatings are used on electrical contacts to prevent sparking and increase their corrosion resistance (palladizing).

In jewelry, palladium is used both as a component of alloys and on its own. In addition, the Bank of Russia mints commemorative coins from palladium in very limited quantities. A small amount of palladium is used for medical purposes - the preparation of cytostatic drugs - in the form of complex compounds, similar to cis-platinum.

The honor of discovering palladium belongs to the Englishman William Hyde Wollaston, who isolated the new metal from raw platinum in South American mines in 1803. Who is this man whose name is given to the pure palladium medal awarded annually by the Geological Society of London?

At the end of the eighteenth century, William Wollaston was one of many obscure London doctors practicing in poor working-class areas. A job that did not generate income could not suit an intelligent and enterprising young man. In those days, a doctor had to have the skills not only of a physician, but also of pharmacy, which in turn presupposed an excellent knowledge of chemistry. W.H. Wollaston turned out to be an excellent chemist - while studying platinum, he invented a new method for making platinum utensils and established its production. It is worth mentioning that in those years, platinum glassware for chemical laboratories was a necessity, because the excitement around scientific discoveries was the same as in the times of alchemists around the philosopher's stone. It is no coincidence that at the turn of the 18th and 19th centuries. About 20 new chemical elements have been discovered!

It is not surprising that the Englishman’s new enterprise began to bring him considerable income, sufficient to leave his unpromising medical practice. The products produced by Wollaston were in demand far beyond the borders of Foggy Albion, allowing the Englishman to engage in new chemical research without worrying about money. While improving the technique of refining and purifying platinum from impurities, the chemist came to the idea of ​​the possibility of the existence of platinum-like metals.

The platinum that Wollaston had to work with was a by-product obtained from washing gold-bearing sands in the distant Colombian Republic. In addition to gold, it contained mercury impurities, which had to be gotten rid of. He dissolved raw platinum in aqua regia, then precipitated only platinum from the solution - with especially pure ammonia NH4Cl. It was then that Wollaston noted that the precipitated solution had a pink tint, which impurities such as gold and mercury could not give. By adding zinc to the colored solution, the chemist obtained a black precipitate, which he dried and then dissolved in aqua regia. It turned out that only part of the black powder dissolved. After diluting the concentrate with water, Wollaston added potassium cyanide, resulting in the formation of a copious orange precipitate that turned gray when heated. The gray sediment was fused into a metal whose specific gravity was less than mercury. By dissolving the resulting metal in nitric acid, Wollaston obtained a soluble part, which was palladium, and an insoluble part, from which he isolated another platinum - rhodium.

Rhodium gets its name from the Greek word for “pink”, because rhodium salts give the solution a pink color. As for palladium, Wollaston named it in honor of an astronomical discovery that occurred earlier. Shortly before the discovery of palladium and rhodium (in 1802), the German astronomer Olbers discovered a small planet in the solar system and named it Pallas in honor of the ancient Greek goddess of wisdom, Pallas Athena.

What did Wollaston do after the discovery of the new element? He did not immediately announce this, but distributed an anonymous advertisement about the sale of the new palladium metal in the store of the mineral dealer Forster. The message about a new noble metal - “new silver” interested many, including the chemist Richard Chenevix. Having a typical hot-tempered and uncontrollable Irish character, Chenevix wanted to expose the “fraudulent trick” and, disregarding the high price, bought a palladium bar and began to analyze it.

Soon the Irishman suggested that the metal was not a new element at all, but was made from platinum by alloying it with mercury according to the method of the Russian scientist A. A. Musin-Pushkin. Chenevix hastened to express this opinion - first in a report read before members of the Royal Society of London, and then in the wider press. In response to this, the anonymous author of the advertisement announced that he was ready to pay 20 pounds sterling to anyone who could artificially prepare a new metal using the method proposed by Chenevix. However, other chemists, and Chenevix himself, with all their efforts, could not find either mercury or platinum in palladium...

Only some time later, Wollaston officially announced that he was the author of the discovery of palladium and described the method of obtaining it from raw platinum. At the same time, he announced the discovery and properties of another platinum metal - rhodium. In addition, he said that he was the anonymous seller of the new metal who appointed a premium for its artificial preparation.

Such an interesting and extraordinary person was William Hyde Wollaston - a little-known London doctor and world-famous chemist - the discoverer of palladium and rhodium.

Finding palladium in nature

Palladium is one of the rarest metals, its average concentration in the earth's crust is 1∙10-6% by mass, but this is twice as much as the gold contained in the earth's crust (5∙10-7%). William Wollaston had to extract palladium from grains of Colombian native platinum - the only mineral known at that time containing palladium. Nowadays, geochemists can name about 30 minerals that contain this noble metal.

Like platinum, the forty-sixth element is found in native form (unlike the other platinoids), and it may contain impurities of other metals: platinum, gold, silver and iridium. In appearance it is quite difficult to distinguish it from native platinum, but it is much lighter and softer than it. Quite often, palladium itself is an impurity in native gold or platinum. Thus, palladium platinum containing 40% palladium was discovered in the ores of Norilsk, and in Brazil (Minas Gerais state) a very rare and little-studied variety of native gold was found - palladium gold or porpecite. In appearance, this mineral is very difficult to distinguish from pure gold, because it contains only 10% palladium.

About a third of the minerals containing palladium have been poorly studied, some of them do not even have names, this is due to the fact that the minerals of all platinum metals form microinclusions in ores and are difficult to access for research. One such mineral is allopalladium. This silvery-white mineral with a metallic sheen is very rare. All the components of this mineral have not yet been fully identified, but spectral analysis showed the content of mercury, platinum, ruthenium and copper in it. The most famous palladium minerals are palladite PdO, stannopalladite Pd3Sn2, stibiopalladite Pd3Sb (contains PtAs2 impurities), braggite (Pd, Pt, Ni) S (16-20% palladium), potarite PdHg. The last of these minerals was found back in 1925 in the diamond deposits of British Guinea. Its composition was established by conventional chemical analysis: 34.8% Pd and 65.2% Hg.

The largest placer deposits of platinum metals (including palladium) are located in Russia - in the Urals. Other palladium-rich countries include the United States (Alaska), Colombia and Australia.

However, the main supplier of the forty-sixth element was the deposits of nickel and copper sulfide ores, in which palladium is a by-product of processing. After all, its content in such ores is three times greater than platinum itself, not to mention its other satellites. Large deposits of such ores are located in Africa (Transvaal) and Canada. In our country, the richest deposits of copper-nickel ores are located in the Arctic (Norilsk, Talnakh).

Palladium is found not only in the depths of our planet, as evidenced by chemical analysis of space “guests”. Thus, in iron meteorites there are up to 7.7 grams of palladium per ton of substance, and in stone meteorites - up to 3.5 grams. And it was discovered on the Sun simultaneously with helium back in 1868.

It is not surprising that, possessing the richest reserves of platinum metal ores, Russia is one of the world's largest producers and exporters of palladium, as well as platinum, nickel and copper. The leadership in this area among Russian companies belongs to MMC Norilsk Nickel. Enterprises owned by the company mine valuable metals on the Taimyr and Kola Peninsulas. The development of deposits in the Krasnoyarsk Territory is underway. It is believed that the deposit of the Taimyr Peninsula is one of the richest in the world in terms of palladium content in sulfide ores. For this reason, the Norilsk Nickel company is the owner of the largest palladium reserves in the world.

Biological properties of palladium

Scientists definitely cannot say anything about the biological role of palladium in living organisms; perhaps further studies of the properties of this platinum will reveal its significance in certain biological processes.

Nevertheless, the role of this element in medicine is quite large. Thus, in some countries (including Russia), a certain amount of palladium is used to obtain cytostatic drugs - in the form of complex compounds, similar to cis-platinum. Immediately after Rosenberg’s discovery of the cytostatic effect of platinum, scientists around the world began to study this phenomenon and synthesize increasingly more effective and safe platinum compounds for medical purposes. In recent years, the world's leading medical institutes and large companies have been trying to find bioactive drugs among other platinum group compounds, including palladium. This noble metal kills and slows down the growth of cancer cells no worse than platinum, but is almost ten times less toxic. Antitumor drugs based on palladium are undergoing the latest clinical trials and may soon be used by oncologists.

Another quite important purpose of palladium and its alloys is associated with the high biological compatibility of this metal - the manufacture of medical instruments, parts of pacemakers and dentures. Already, the use of traditional non-precious alloys based on cobalt, nickel and chromium for orthopedic dentistry is significantly reduced due to frequent cases of adverse reactions in a number of patients sensitive to the influence of base metals.

What will replace outdated materials? The answer is obvious - alloys of noble metals, including platinum group metals and palladium in particular. One such alloy is palladent (“Superpal”), containing 60% palladium and 10% gold. The alloy has a beautiful silver-gray metallic color, reliable strength characteristics, and is biologically compatible. In maxillofacial surgery it is used for the manufacture of extended bridges. Another alloy containing palladium is plagodent ("Super KM"). It consists of 98% of noble metals (except for palladium, it contains gold and platinum), has a light yellow color and is intended for the manufacture of solid dentures, inlays, half-crowns, bridges, mainly with ceramic or glass-ceramic coating.

Palladium is also used by the food industry. After it became clear in a number of countries that nickel was the cause of a surge in allergies among the population, many blamed dishes made from this material. However, subsequent studies refuted this hypothesis and established the true cause of the allergic reaction - nickel was found in food, or more precisely in margarine made from vegetable oil. The fact is that according to the technological process, the oil must become solid; for this it is hydrogenated, that is, the molecules are saturated with hydrogen using a catalyst. Nickel has played this role for a long time. To intensify the process, the catalyst powder is intensively mixed with vegetable oil at high temperature, and then the catalyst is removed by filtration, however, nickel is not completely removed, and if a failure occurs in the process, a fairly large amount of this allergen enters the final product.

This problem was solved thanks to the developments of scientists from the Petrochemical Institute named after A.V. Topchieva. They managed to create a catalyst based on palladium supported on aluminum oxide. This introduction made it possible to solve several problems at once: palladium is inert and safe for humans, in addition, it is many times more effective than nickel, which means that it is needed thousands of times less. There are other advantages of a palladium catalyst - it is easier to remove from the final product and the structure of the molecules of the latter is “deciphered” by the body more easily than in the case of a nickel catalyst, so “palladium” margarine is easier to digest.

Palladium is a noble platinum metal of silver-white color with a face-centered cubic lattice like copper (a = 0.38902 nm, z = 4). Being part of the first triad of platinum group metals, palladium is still more similar in appearance to silver than to platinum. At the same time, all three metals are very similar in appearance, but the same cannot be said about their density. In this aspect, palladium (density 12.02 g/cm3) is much closer to silver (10.49 g/cm3) than to platinum (21.5 g/cm3).

In addition to the fact that the forty-sixth element is the lightest of the platinum metals, it is also the most fusible of them - the melting point of Pd is 1,552 ° C, while the melting point of platinum (Pt) is 1,769 ° C, the melting point of rhodium ( Rh) 1,960 °C, the melting point of ruthenium (Ru) is 2,250 °C, for iridium (Ir) the melting point is 2,410 °C, and the melting point of osmium (Os) exceeds 3,000 °C. The situation is the same with the boiling point of platinum metals - the lowest is for palladium (3,980 °C), for rhodium and platinum about 4,500 °C, for ruthenium about 4,900 °C, and for iridium (5,300 °C) and osmium (5,500 °C) the highest boiling points of all platinoids.

Other temperature characteristics of the forty-sixth element: heat capacity (at a temperature of 0 °C) 0.058 cal/(g∙°C) or 0.243 kJ/(kg∙K); thermal conductivity 0.17 cal/(cm∙sec∙°C) or 71 W/(m∙K). The linear coefficient of thermal expansion at 0 °C is 11.67∙10-6.

The similarity in appearance of palladium with silver and platinum, its ability to be well polished, resistance to corrosion and, as a result, lack of tarnishing - all these qualities have made the forty-sixth element one of the jewelry metals. In a palladium frame, precious stones stand out effectively. Watches in white gold cases are very popular. It would seem what does palladium have to do with it? The fact is, “white gold” for watch cases is gold that has been bleached by the addition of palladium. The ability of palladium to “bleach” large amounts of gold is well known. Palladium also has a beneficial effect on other metals. Thus, its addition to titanium (less than 1%) can transform this metal into an alloy absolutely resistant to aggressive environments. Pure titanium is able to resist aqua regia and nitric acid, but is unstable to concentrated hydrochloric and sulfuric acids. Alloyed with palladium, titanium easily withstands their influence.

Like platinum, palladium is a ductile and malleable metal that can be easily welded, rolled, drawn, stamped and drawn even at room temperature. For heated palladium, these qualities are improved; it is possible to obtain the thinnest sheets, wire, and seamless pipes of the required length and diameter from it. Brinell hardness 49 kgf/mm2. The normal elastic modulus for the forty-sixth element is 12600 kgf/mm2. Elongation at break 24-30%. Tensile strength 18.5 kgf/mm2. It is noteworthy that the mechanical characteristics of palladium are not constant, which is important for technology. So, after cold working, the hardness of this metal increases by 2-2.5 times, but decreases after annealing. Additions of related metals also affect the properties of palladium: the addition of 4% ruthenium and 1% rhodium doubles the tensile strength!

Like all platinum metals, palladium is paramagnetic, its magnetic susceptibility χs∙10-6 (at a temperature of 18 °C) is equal to 5.4 electromagnetic units. The electrical resistivity at 0 °C is 10 Ohm∙cm∙10-6. Palladium has a unique ability to absorb hydrogen: more than eight hundred volumes of hydrogen dissolve in one volume of palladium under normal conditions. In this case, the element retains its metallic appearance, but cracks and becomes brittle.

Before describing the chemical properties of palladium, it is necessary to mention that this is the only element with an extremely filled outer electron shell: there are 18 electrons in the outer orbit of the palladium atom. What is the importance of this fact? The fact is that with such a structure, an atom simply cannot but have the highest chemical resistance. Therefore, even the all-destructive fluorine does not affect palladium under normal conditions. In compounds, palladium can be di-, tri- and tetravalent, most often divalent. At the same time, the forty-sixth element is the most active of the platinum metals, similar in chemical properties to platinum. In air, palladium is stable up to a temperature of 300-350 °C/

Interestingly, having “passed” the threshold of 850 °C, palladium oxide PdO decomposes into metal and oxygen, and at this temperature metallic palladium becomes resistant to oxidation again.

Palladium does not react with water, dilute acids, alkalis, or ammonia hydrate. This is explained by the position of the forty-sixth element in the series of standard potentials, where it is to the right of hydrogen. At room temperature, palladium reacts with wet bromine and chlorine.

At temperatures of 500 °C and above, the forty-sixth element can interact with fluorine and other strong oxidizing agents, as well as with sulfur, selenium, tellurium, arsenic and silicon.

The interaction of palladium with hydrogen is very interesting - the metal is capable of absorbing large amounts of this gas (at room temperature, one volume of palladium absorbs up to 950 volumes of hydrogen) due to the formation of solid solutions with an increase in the crystal lattice parameter. Hydrogen is found in the metal in atomic form and has high chemical activity. The absorption of a large volume of hydrogen does not leave its mark on palladium - the metal swells, swells, and cracks. The absorbed gas is easily removed from palladium when heated to 100 °C in a vacuum.

In addition to absorbing hydrogen, palladium has the property of transiting this gas through itself. So, if hydrogen is pumped under pressure into a vessel made of palladium, and then the sealed container is heated, then the hydrogen will “flow out” from the palladium vessel through the walls, like water through a sieve. At 240 °C, 40 cubic centimeters of hydrogen pass through every square centimeter of a millimeter-thick palladium plate in one minute, and with increasing temperature the permeability of the metal becomes even more significant.

Like all platinum metals, palladium forms many complex compounds. Complexes of divalent palladium with amines, oximes, thiourea and many other organic compounds have a flat, square structure and this differs from complex compounds of other platinoids. They almost always form bulky octahedral complexes. Modern science knows more than one thousand palladium complex compounds. Some of them bring practical benefits - at least in the production of palladium itself.

It is known that palladium is often used by jewelers in alloys with other precious metals. Thus, alloys of 583 and 750 samples, called “white gold,” can contain ten percent palladium or more. In our country, the government has officially established palladium hallmarks of 500 and 850. These hallmarks are the most common in jewelry.

Another popular palladium standard is 950. This is due to the fact that wedding rings are made from this metal as an alternative to white gold rings with rhodium plating. The fact is that rhodium wears off quite quickly from the surface of the ring, and not everyone will be able to renew the expensive coating every year. Palladium rings have exactly the same appearance as gold ones, but do not require annual renewal. In addition to standard palladium alloys, jewelry production sometimes uses decorative compounds of palladium with indium, forming a wide range of colors from golden to lilac. However, products made from such an alloy are very rare.

In 1988, 25-ruble coins were minted from palladium for the first time in the series “1000th anniversary of ancient Russian coinage, literature, architecture, and the baptism of Rus'.” The coin weighing 31.1 g of the highest 999 standard depicts a monument to Prince Vladimir Svyatoslavovich in Kyiv. In Basel, at the International Numismatic Exhibition, this series was recognized as the best program of the year, receiving first prize for quality of execution.

The release of such coins was limited and did not last long, for this reason the coins have a high collectible value. The most valuable are two series of coins (issued 1993-1994): “The first Russian trip around the world. 1803-1806" - "The sloop "Nadezhda"" with a portrait of I.F. Krusenstern, "The sloop "Neva" (Yu.F. Lisyansky)." Second series “The first Russian Antarctic expedition. 1819-1821" - "Sloop "Mirny" (M.P. Lazarev)", "Sloop "Vostok" (F.F. Bellingshausen)". Also presented are coins from the “Russia and World Culture” series - “A. Rublev", "M. P. Mussorgsky”, coins of the “Russian Ballet” series and dedicated to Russian monarchs.

There are many awards and prizes in the world that are awarded to outstanding scientists. There is a medal named after William Hyde Wollaston, made of pure palladium. This award was established almost two centuries ago (1831) by the Geological Society of London and was initially made of gold. Only in 1846, the famous English metallurgist Johnson extracted pure palladium from Brazilian palladium gold, intended exclusively for the manufacture of this medal. Those awarded the Wollaston Medal included Charles Darwin, and in 1943 the medal was awarded to the Soviet scientist Academician Alexander Evgenievich Fersman for his outstanding mineralogical and geochemical research. Now this medal is kept in the State Historical Museum.

However, this is not the only palladium medal. The second, awarded for outstanding work in the field of electrochemistry and the theory of corrosion processes, was established by the American Electrochemical Society. In 1957, this award recognized the works of the largest Soviet electrochemist, Academician A.I. Frumkin.

The merits of William Wollaston include not only the discovery of palladium (1803) and rhodium (1804), the production of the first pure platinum (1803), but also the discovery of ultraviolet radiation, independent of I. Ritter. In addition, Wollaston designed a refractometer (1802) and a goniometer (1809).

The palladium industry in Russia appeared relatively late. Only in 1922 did the State Refinery produce the first batch of Russian refined palladium. This marked the beginning of the industrial production of palladium in our country.

It is known that palladium can enhance the anti-corrosion properties of even such a metal as resistant to aggressive environments as titanium. The addition of palladium of only 1% increases the resistance of titanium to sulfuric and hydrochloric acids. So, over a year of exposure to hydrochloric acid, a plate of the new alloy loses only 0.1 millimeters of its thickness, while pure titanium thins by 19 millimeters over the same period. A calcium chloride solution has no effect on the alloy at all, while titanium loses up to two millimeters annually in an aggressive environment. What is the secret of such an alloy? The fact is that the acid interacts primarily with palladium and immediately the surface of the second component of the alloy is covered with a thin oxide film - the part, as it were, puts on a protective jacket. This phenomenon was called by scientists self-passivation (self-defense) of metals.

Another very valuable property of palladium is its relatively low price. So at the end of the sixties of the last century it cost about five times less than platinum. Over time, the price of the forty-sixth element increased, but the prices of other noble metals also increased. It is this quality of palladium that makes it the most promising of all platinum metals, expanding the scope of its use.

Palladium, like other platinum metals, is an excellent catalyst. In its presence, many practically important reactions begin and proceed at low temperatures, for example, the processes of hydrogenation of fats and cracking of oil. Palladium accelerates the hydrogenation processes of many organic products much better than a proven catalyst such as nickel. The forty-sixth element is used as a catalyst in the production of acetylene, many pharmaceuticals, sulfuric, nitric, acetic acids, fertilizers, explosives, ammonia, chlorine, caustic soda and other products of organic synthesis.

In chemical production equipment, a palladium catalyst is most often used in the form of “black” (in a finely dispersed state, palladium, like all platinum metals, becomes black) or in the form of PdO oxide (in hydrogenation apparatuses). Since the seventies of the 20th century, palladium has been actively used by the automotive industry in exhaust gas afterburning catalysts (neutralizers). By the way, neutralizers are necessary not only for cleaning car exhaust gases, but also for cleaning any gas emissions, for example, at thermal power plants. Industrial installations for this purpose are used in the USA, some EU countries and Japan.

Due to the fact that hydrogen actively diffuses through palladium, the latter is used for deep purification of hydrogen. Under slight pressure, the gas is passed through palladium tubes, closed on one side, heated to 600 ° C. Hydrogen quickly passes through the palladium, and impurities (water vapor, hydrocarbons, oxygen, nitrogen) are retained in the tubes. To reduce the cost of the process, not pure palladium is used, but its alloys with other metals (silver, yttrium).

Applications of palladium in the electronics industry

Palladium and its alloys are widely used in electronics for sulfide-resistant coatings. A certain amount of this metal is used for the production of high-precision precision resistance rheochords (aerospace and military equipment), including in the form of an alloy with tungsten (for example, PdV-20M). In its pure form, palladium is part of ceramic capacitors with high temperature stability of the capacitance, which are used in the production of pagers, mobile phones, computers, wide-screen TVs and other electronic devices. Palladium chloride PdCl2 is used as an activating substance in the galvanic metallization of dielectrics - in particular, the deposition of copper on the surface of laminates in the production of printed circuit boards in electronics.

The forty-sixth element is also needed in jewelry, both as a component of alloys and on its own. For example, the well-known concept of “white gold” refers to an alloy of gold, palladium and some other elements. For example, “white gold” of 583 standard contains 13% palladium, and white precious metal of 750 standard has the following composition: Au – 75%, Ag – 4%, Pd – 21% (for this sample the composition may vary). “Pure” palladium jewelry contains an admixture of 5% ruthenium.

Use of palladium in everyday life

Palladium is used for the manufacture of special chemical vessels (for example, for the production of hydrofluoric acid) - distillation cubes, vessels, pump parts, retorts. Part of the metal is spent on the manufacture of corrosion-resistant parts of high-precision measuring instruments.

In the glass industry, palladium alloys are used in crucibles for glass melting and in dies for producing artificial silk and viscose thread.

Use of palladium in medicine

Palladium and its alloys are also used in medicine - the manufacture of medical instruments, parts for pacemakers, and dentures. In some countries, a small amount of palladium is used to obtain cytostatic drugs - in the form of complex compounds, similar to cisplatin.

Application of palladium in the jewelry industry

Palladium is beautiful in its own way, polishes well, does not tarnish and is not susceptible to corrosion. In a palladium frame, precious stones, especially diamonds, stand out effectively. Today, jewelry made of palladium, as well as white gold, is very popular. Here, “white gold” must be understood in the literal sense of the word: it is gold bleached by the addition of palladium. Palladium can “bleach” almost six times the amount of gold.

Palladium is not often seen as a base for jewelry - this precious metal serves as a component of various jewelry alloys. It is often used in the production of white gold or as the base of a palladium alloy. The fact is that even 1-2% palladium is enough for gold to acquire a silvery-white hue (the nickel additive provides a yellowish color, and rhodium gives a slight blue). But most often 14k white gold contains 13% palladium. It is perfect for setting diamonds.

And when added to platinum, palladium provides ductility to the metal. The metal itself is too soft to be used in its pure form. Therefore, alloys are the most optimal solution for this noble metal, as well as for others.

In nature, palladium is found together with platinum; it can be extracted using a special technology. In appearance, palladium resembles silver. In 1803 it was called “new silver” because of its silvery hue. However, this is where the similarity ends - the chemical and physical-mechanical properties of silver and palladium differ like heaven and earth. Although palladium does not oxidize in air and is not exposed to external factors, it is easily dissolved in nitric and sulfuric acids. In general, one can note its extraordinary malleability - from one gram of palladium you can pull out the longest wire and roll out the thinnest sheet.

Therefore, ductile palladium has found application in the electronics industry, in instrument making, and, of course, in the jewelry industry. On world markets, palladium is listed along with gold, silver and platinum.

When making jewelry, it is not pure palladium that is used, but its alloy with various chemical elements, the most common of which are nickel, cobalt and ruthenium. The Russian government has officially established 500 and 850 samples of palladium. These are the most common hallmarks found on most jewelry.

In addition, 950 hallmark is very popular, from which wedding rings are often made, as an alternative to white gold with rhodium plating. Rhodium quickly wears off with constant contact with the skin of your hands, and going to a jewelry workshop every year to renew the coating is not acceptable for everyone. Palladium rings have exactly the same appearance as gold rings, but they do not need to be treated every year.

Use of palladium as money

Their production was completed several years ago and did not last long, so these coins have a high collector's value. The series “The first Russian trip around the world. 1803-1806" - "Sloop "Nadezhda"" with a portrait of I.F. Kruzenshtern, “The Sloop “Neva” (Yu.F. Lisyansky)” and the series “The First Russian Antarctic Expedition. 1819-1821” – “Sloop “Mirny” (M.P. Lazarev)”, “Sloop “Vostok” (F.F. Bellingshausen)”. The coinage quality is “proof”, the content of pure metal in the coin is 31.1 g, the denomination is 25 rubles, issued in 1993-94. Also presented are coins from the “Russia and World Culture” series – “A. Rublev”, “M.P. Mussorgsky”, coins of the “Russian Ballet” series and dedicated to Russian monarchs. Quantity is limited. In addition to their rarity, palladium coins can serve as a gaming investment tool - since 1997, prices for palladium on the world market have ranged from $150 to $1,000 per troy ounce.

A quarter of a century later, the following message appeared in the Mining Journal published in Russia: “In 1822, G. Brean had an order from the Spanish government to purify and turn into ingots all the platinum collected in America for many years. On this occasion, processing more than 61 pounds of raw platinum, he separated two and a quarter pounds of palladium, a metal discovered by Wollaston and, due to its extreme rarity, valued five and a half times more than gold.”

Today, when the content of all elements in the earth's crust has been calculated with relative accuracy, it is known that there is approximately ten times more palladium in it than gold. However, the total reserves of palladium, like other platinum group metals, are quite meager - only 5-10 - 6%, although geochemists can name about 30 minerals that contain this element. Unlike other platinoids, palladium, like platinum itself, is also found in the native state. As a rule, it contains impurities of platinum, iridium, gold, and silver. Often palladium itself is found in nature as an admixture to native platinum or gold. In Brazil, for example, a rare variety of native gold (porpecite) was found, which contains 8 - 11% palladium.

Since alluvial deposits of palladium are quite rare, the main raw materials for its production are nickel and copper sulfide ores. Palladium, however, plays a modest role as a by-product of ore processing, but this does not make it any less valuable. Transvaal and Canada have large deposits of such ores. And relatively recently, Soviet geologists discovered extensive deposits of copper-nickel ores in the Norilsk region, which are characterized by the presence of platinum metals, mainly palladium.

This element is found not only on our planet - it is also found on other celestial bodies, as evidenced by the composition of meteorites. Thus, in iron meteorites there are up to 7.7 grams of palladium per ton of substance, and in stone meteorites - up to 3.5 grams. Everyone knows that there are spots on the Sun. But what's on the Sun

there is palladium, apparently not everyone knows. Scientists discovered palladium there at the same time as helium, back in 1868.

Despite the fact that palladium is approximately one and a half times heavier than iron, among its “colleagues” the platinum group metals it is known as lightweight: in terms of density. (12 g/cm3) it is significantly inferior to osmium (22.5), iridium (22.4), and platinum (21.45). It also melts at a lower temperature (1552° C) than other platinum group metals. Palladium is easily processed even at room temperature. And since it is quite beautiful, polishes well, does not tarnish or corrode, jewelers willingly took it to work: for example, they make frames for precious stones from it.

We are already accustomed to such newspaper cliches as “black gold” - this is how oil is called, “soft gold” - fur, “green gold” - forest. When people talk about “white gold,” they usually mean cotton. But it turns out that gold can be white in the most literal sense: even small additions of palladium remove the yellowness from the “face” of gold and give it a beautiful white tint. Watches, settings for precious stones, bracelets made of white gold are very impressive.

The acquaintance with palladium for titanium was very pleasant. It is known that this metal is characterized by high corrosion resistance: even such omnivorous “predators” as aqua regia or nitric acid cannot “feast” on titanium, but under the influence of concentrated hydrochloric and sulfuric acids it is still forced to correlate. But if it is slightly “vitaminized” with palladium (the addition is less than 1%), then the ability of titanium to resist these oxidizing agents increases sharply. This alloy has already been mastered by our factories: equipment for the chemical, nuclear, and oil industries is made from it. Over the course of a year in hydrochloric acid, a plate of the new alloy loses only 0.1 millimeters of its thickness, while pure titanium “loses” by 19 millimeters over the same period. The alloy is not at all tough for a solution of calcium chloride, and titanium without an admixture of palladium has to pay an annual tribute to this aggressor - more than two millimeters.

How does palladium manage to have such a beneficial effect on titanium? The reason for this turned out to be the phenomenon of the so-called self-passivation (self-protection) of metals, recently discovered by scientists: if literally microdoses of noble metals - palladium, ruthenium, platinum - are introduced into alloys based on titanium, iron, chromium or lead, then the resistance of the alloys against corrosion increases by hundreds, thousands and even tens of thousands of times.

In the Alloy Corrosion Laboratory of the Institute of Physical Chemistry, scientists tested the effect of palladium on chromium steel. Parts made of this material are corroded by many acids within a few days. The fact is that positive metal ions pass into the acid solution, and hydrogen ions penetrate from the solution into the crystal lattice of the metal and readily combine with free electrons. The resulting hydrogen is released and destroys the steel. When a part made of the same steel, but with a “homeopathic” addition of palladium (a fraction of a percent), was immersed in acid, the corrosion of the metal lasted only... a few seconds, and then the acid turned out to be powerless. The study showed that the acid interacts primarily with palladium and immediately the surface of the steel is covered with a thin oxide film - the part, as it were, puts on a protective jacket. This “armor” makes steel practically invulnerable: its corrosion rate in boiling sulfuric acid does not exceed tenths of a millimeter per year (previously it reached several centimeters).

Palladium itself is also easily influenced by some other elements: once you introduce into it, for example, a small amount of related metals - ruthenium (4%) and rhodium (1%), its tensile strength approximately doubles.

Alloys of palladium with other metals (mainly silver) are used in dental technology - excellent dentures are made from it. Palladium covers especially critical contacts of electronic equipment, telephones and other electrical devices. Palladium is used to make dies - caps with many tiny holes; in the production of the finest wire or artificial fibers, a specially prepared mass is forced through these holes. Palladium is used as a material for thermocouples and some medical instruments.

But perhaps of greatest interest are the unique chemical properties of palladium. Unlike all elements known to science today, it has 18 electrons in the outer orbit of the atom; in other words, its outer electron shell is filled to capacity. This atomic structure determined the exceptional chemical resistance of palladium: even the all-destructive fluorine under normal conditions is no more dangerous to it than a mosquito bite to an elephant. Only by calling on high temperatures (500° C or more) for help can fluorine and other strong oxidizing agents interact with palladium. Palladium is capable of absorbing or, in the language of physicists and chemists, occluding certain gases, mainly hydrogen, in large quantities. At room temperature, a cubic centimeter of palladium can absorb approximately 800 “cubes” of hydrogen. Of course, such experiments do not leave their mark on the metal: it swells, swells, and cracks.

No less surprising is another property of palladium, also associated with hydrogen. If, for example, you make a vessel from palladium and fill it with hydrogen, and then, after sealing it, heat it, the gas will calmly begin to flow through... the walls of the vessel, like water through a sieve. At 240°C, in one minute, 40 cubic centimeters of hydrogen pass through every square centimeter of a millimeter-thick palladium plate, and with increasing temperature, the permeability of the metal becomes even more significant.

Like other platinum metals, palladium serves as an excellent catalyst. This property, combined with the ability to transmit hydrogen, underlies a phenomenon recently discovered by a group of Moscow chemists. We are talking about the so-called conjugation (mutual acceleration) of two reactions on one catalyst, which is palladium. In this case, the reactions seem to help each other, and the substances taking part in them do not mix.

Imagine a device hermetically separated by a thin palladium partition (membrane) into two chambers. One of them contains butylene, the other contains benzene. Palladium, hungry for hydrogen, pulls it out of the butylene molecules, the gas passes through the membrane into another chamber and there readily combines with benzene molecules. Butylene, from which hydrogen has been taken away, turns into butadiene (the raw material for the production of synthetic rubber), and benzene, having absorbed hydrogen, becomes cyclohexane (nylon and nylon are made from it). The addition of hydrogen to benzene proceeds with the release of heat; This means that in order for the reaction not to stop, heat must be removed all the time. But butylene is ready to give up its hydrogen only “in exchange” for a certain number of joules. Since both reactions take place “under one roof,” all the heat generated in the first chamber is immediately used in the other. The effective combination of these chemical and physical processes is made possible by a thin palladium plate.

Using membrane palladium catalysts, it is also possible to obtain ultra-pure hydrogen from petroleum feedstocks and associated gases, which is necessary, for example, for the production of semiconductors and highly pure metals.

These days, palladium is relatively cheap - its price is five times less than platinum. An important circumstance! It allows us to hope that there will be more and more work for this metal every year. And electronic computers will help him find new areas of activity. Solving such problems is within the capabilities of computers, of course, provided that scientists provide them with the necessary “information for thought.”

Today, no one will be surprised by the fact that computers play chess, control technological processes, translate from foreign languages, and calculate the flight trajectories of spacecraft. Why not make it a duty?

The use of palladium in computers

Computer creation of new alloys with unique properties?

Scientists at the A. A. Baikov Institute of Metallurgy set themselves this problem several years ago. First of all, they had to find a common language with the machine in which they could give commands to it. And scientists managed to develop such a language - the necessary algorithms. The results of studies of approximately 1,500 different alloys and, in addition, “profile data” of metals - the electronic structure of their atoms, melting temperatures, types of crystal lattices and many other information characteristic of each of the metals were entered into the memory block of the Minsk-22 computer. Knowing all this, the machine had to predict which previously unknown compounds could be obtained, indicate their basic properties, and therefore select suitable areas of application for them.

Imagine that these problems would be solved, as before, “manually” - through ordinary experiments. This would mean that to each metal it is necessary to add various amounts of another metal, selected for one reason or another, to prepare samples from the resulting alloys, then subject them to physical and chemical studies, etc. Well, if you set out to study all possible combinations of not two, but three, four, five components? Such work would take tens, or even hundreds of years. In addition, conducting experiments would require a huge amount of metals, many of which are expensive and scarce. It is quite possible that the earth’s reserves of such rare elements as, for example, rhenium, indium, palladium, would simply not be enough for such experiments.

An electronic computer provides food for the mind with numbers, symbols, formulas, and its “labor productivity” is higher: in a matter of moments it is able to produce enormous scientific information.

As a result of painstaking work carried out under the leadership of Corresponding Member of the USSR Academy of Sciences E. M. Savitsky, it was possible to first predict using a computer and then obtain in situ many interesting materials. One of the first compounds born by computers were palladium alloys, including the unusually beautiful lilac alloy of palladium and indium. But the main thing, of course, is not the color. The business qualities of the new “employees” are much more important. And they, I must say, are at their best. Thus, the palladium-tungsten alloy created by the institute made it possible to increase the reliability and service life of many electronic devices by more than 20 times.

“Forecasting using a computer,” says E.M. Savitsky, “of course, is not done for alloys that can be obtained by simply mixing components, but where complex compounds are needed and it is required to obtain alloys that can withstand enormous pressures and ultra-high temperatures that resist magnetic and electric fields, where the help of a computer is needed.” The machine has already suggested to scientists about eight hundred new superconducting compounds and almost a thousand alloys with special magnetic properties. In addition, the computer recommended that metal scientists pay attention to approximately five thousand compounds of rare earth metals, of which only a fifth are still known. Valuable instructions were received from the machine also regarding transuranium elements.

According to E. M. Savitsky, “the possibilities for the synthesis of inorganic compounds are limitless. Based on them, in the coming years the number of compounds obtained can be increased tenfold. And undoubtedly among them there will be substances with completely new and rare physical and chemical properties necessary for the national economy and new technology.”

In conclusion, we will talk about two medals made of palladium. The first of them, bearing the name of Wollaston, was established by the Geological Society of London a century and a half ago. At first the medal was minted from gold, but after the English metallurgist Johnson extracted pure palladium from Brazilian palladium gold in 1846, it was made only from this metal. In 1943, the Wollaston medal was awarded to the remarkable Soviet scientist Academician A.E. Fersman and is now kept in the State Historical Museum of the USSR. The second palladium medal, awarded for outstanding work in the field of electrochemistry and the theory of corrosion processes, was established by the American Electrochemical Society. In 1957, this award recognized the works of the largest Soviet electrochemist, Academician A.I. Frumkin.

Palladium production

We know that William Hyde Wollaston isolated palladium while studying the latest methods of refining platinum. Dissolving raw platinum in aqua regia and precipitating only pure noble metal from the solution with ammonia, the chemist noted the unusual pink color of the solution. A color of this kind could not be explained by the presence of known impurities in raw platinum, from this Wollaston concluded that some platinum metals were present in the samples of the ore he studied.

Having treated the resulting solution of an unusual color with zinc, the English chemist obtained a black precipitate, which he dried and tried to re-dissolve in aqua regia. However, not all the powder was dissolved. By diluting this solution with water and adding potassium cyanide (to avoid precipitation of small amounts of platinum remaining in the solution), William Wollaston obtained an orange precipitate, which when heated became gray in color, and when fused, it turned into a drop of metal, which the scientist tried to dissolve in nitric acid. The soluble part was palladium.

The scientist himself described the discovery of a new metal in such complex and obscure language. Modern methods for obtaining pure palladium from natural raw materials, based on the separation of chemical compounds of platinum metals, are very complex and time-consuming. Most companies and corporations involved in refining are not willing to share their production secrets. We can only say that the production of palladium is one of the stages in the processing of raw platinum and the production of platinum metals. The metal is obtained according to the following scheme: from the filtrate remaining after the precipitation of (NH4)2, as a result of refining, the sparingly soluble complex compound dichlorodiammine palladium Cl2 is obtained, it is purified from impurities of other metals by recrystallization from an NH4Cl solution.

Sponge palladium is smelted in a high frequency vacuum electric furnace. By reducing solutions of palladium salts, fine-crystalline palladium is obtained - palladium black.

Other refining methods are also used, in particular, those based on the use of ion exchangers. It is known that in the mid-eighties of the last century, the annual mining and production of palladium in Western and developing countries was about 25-30 tons. No more than ten percent of palladium was obtained from recycled materials. At the same time, the USSR accounted for up to two-thirds of the total world production of the precious metal. In our time (according to 2007), palladium production amounted to 267 tons, of which Russia accounted for 141 tons, South Africa - 86 tons, the USA and Canada - 31 tons, other countries - 9 tons. From these statistics it is clear that production, as well as the extraction of the forty-sixth element, is increasing, and the role of the leader still remains with our country.

Palladium products are mainly produced by stamping and cold rolling. From this metal it is quite easy to obtain seamless pipes of the required length and diameter. In addition, palladium is produced in ingots of 3000-3500 grams, as well as in the form of tapes, strips, foil, wire and other semi-finished products.

The metal trading market is experiencing rapid growth in demand for palladium. It is possible that soon the existing supply on the market will no longer be enough to satisfy the growing demand for the metal, as a result of which the price of palladium will rise even higher. Thus, palladium becomes the best investment among precious metals.

Palladium is a profitable investment

The metal trading market has seen an increase in demand for palladium since 2006. It is possible that the existing supply on the market will soon be insufficient to meet the growing demand for the metal, causing the price of palladium to rise even higher. Thus, palladium becomes the best investment among precious metals.

Palladium is a platinum group metal with unique properties that are especially valuable for solving research and production problems. When palladium is added to titanium or chromium steel, its high corrosion resistance becomes almost absolute. Alloys with palladium are used to make materials for the chemical, nuclear, and oil refining industries.

Like other platinum group metals, palladium is an excellent catalyst. This property has found wide application in the automotive industry. Palladium has an amazing ability to absorb certain gases, especially hydrogen. Thanks to this, it is beginning to be used in the development of fuel cells for hydrogen energy. With the development of technology, the consumption of platinum and palladium has increased more than 20 times in the last half century. In addition, palladium is also very beautiful and easy to process. It resembles platinum, but weighs less and has an even, bewitching shine. An extremely rare metal, it is mined from ores that usually also contain gold, nickel, copper, and is sometimes found in native form. The main raw materials for its production are copper-nickel ores, during the processing of which palladium is a by-product.

Almost all of the world's reserves of ores containing platinum group metals belong to Russia and South Africa, moreover, South African ores contain more platinum, and Russian ores contain more palladium. Small amounts of palladium are also found in the depths of Canada, the USA, Zimbabwe, China and Finland. The largest proven reserves of palladium are located beyond the Arctic Circle. According to the Norilsk Nickel company, proven and probable ore reserves in deposits on the Taimyr Peninsula contain 62 million ounces of palladium and 16 million ounces of platinum. (Russia - Canada: competition in the non-ferrous metals market).

Since the 1970s, the automotive industry has become the main application of platinum group metals. Platinum, palladium and rhodium are used in the production of catalysts used to reduce the toxicity of exhaust gases. For a long time, platinum was used almost exclusively for this. Catalyst manufacturers such as Johnson Matthey, who had close ties to South African mining companies, were interested in this. They deliberately did not use cheaper palladium - moreover, South Africa does not have much of it - and thereby helped maintain the high position of their suppliers, while they themselves remained practically a monopoly.

The situation began to change in 1988, when the Ford Motor Company (F) mastered the production of catalysts using palladium instead of platinum. By the mid-nineties, both metals were already used to approximately equal extent for the production of autocatalysts. With stricter environmental requirements, consumption of platinum metals continues to grow. Over the past 5 years, the world's largest automakers have increased the use of palladium in vehicle exhaust systems by 32%.

In the 1990s, palladium began to rapidly replace platinum in the industry. While in 1990, almost six times more platinum than palladium was used in the production of autocatalysts, then in 1995 palladium began to predominate, and in 1999 the ratio became 4 to 1 in favor of palladium. The “Decade of Palladium” (1990–1999) coincided with a period of widespread use of autocatalysts throughout the world. The corresponding increase in demand for platinum metals from the automotive industry has been met almost entirely by palladium, with relatively stable levels of platinum use. In the physical dimension, the use of PGMs in autocatalysts has increased almost 4 times over 10 years, and palladium - 25 times!

In the first half of the 1990s, the increase in demand for palladium was covered by existing production capacity, and prices remained at the level of 100 - 150 dollars / ounce, i.e. 3 – 4 times lower than for platinum. But a further increase in demand led to a shortage of palladium on the market starting in 1997, which led to a significant increase in prices. In 1999, the cost of palladium equaled the cost of platinum, and in 2000 it became more expensive than platinum - a clear sign of market overheating. Manufacturers of autocatalysts were forced to refocus on platinum, reducing purchases of palladium.

In recent years, the price gap between platinum and palladium has remained in the range of 3.5-5 and is still very far from the normal price ratio (approximately 1 to 2).

Meanwhile, given the low price of palladium compared to platinum, demand for palladium from autocatalyst manufacturers is growing again. According to Johnson Matthey, in 2008, demand for palladium for use in autocatalysts increased by 0.9 tons to 142.3 tons.

In the beauty space, palladium is beginning to overtake platinum. Palladium is beautiful in itself, and adds nobility to other metals: small additions of it give gold a unique white tint; “white gold” serves as an excellent setting for precious stones. According to Fortunoff, the largest trading house and jewelry manufacturer from New York, palladium products already account for 10% of the jewelry market. According to Johnson Matthey, in the jewelry industry, demand for palladium increased by 1.7 tons to 24.3 tons in 2008, after falling for two years in a row. Fortunoff spokeswoman Ruth Fortunoff says: “We definitely expect continued sales growth. People don’t yet come specifically for palladium jewelry, but once they see the prices and become familiar with the metal, they become fans of it.” The average price of a palladium engagement ring is approximately $600, while a ring made of platinum costs twice as much. In times of crisis, this becomes especially relevant.

Exchange-traded funds are beginning to play a special role in the precious metals market. Their shares, backed by precious metals, are listed on an exchange and traded in the same way as corporate shares. Analysts believe that the new funds will increase demand for precious metals and attract additional investment.

Indeed, the creation of new exchange-traded funds, which themselves have become active buyers of platinum, remains one of the main factors behind the significant increase in the price of platinum. Since both the properties and applications of palladium and platinum largely coincide, the markets for these metals are interconnected, which means we can expect a similar reaction of the palladium market to the activities of the funds.

Such assumptions are confirmed by Stuart Flerlage from the New York company NuWave Investment: “Platinum prices are rising higher and higher... Perhaps we will see the same picture with palladium prices.” The creation of exchange-traded funds linked to the price of platinum could further fuel demand for the metal, prompting more manufacturers and jewelers to turn their attention to the still more affordable palladium, said Michael Gambardella, an analyst at JPMorgan Chase & Co. (JPM). “We expect the large price gap between the two metals to narrow,” adds Gambardella.

Sources and links

wikipedia.org – the largest free encyclopedia

helprf.com - Financial support center

interfax.ru - news portal

ru.goldsilvermetals.com - physical metals and their properties

i-think.ru - chemical reference book and metal trade

globfin.ru - world economy, finance and investment

xumuk.ru - chemical encyclopedia

forexpf.ru - site about online trading

ru.investing.com - the largest investment site

all-currency.ru - official foreign currency rates

alhimik.ru - site about chemicals

chemistry-chemists.com - magazine of chemist enthusiasts

Palladium is one of the elements of the periodic table, part of the platinum group

The history of the discovery of palladium and its occurrence in nature, the biological, chemical and physical properties of palladium, the use of palladium in the jewelry industry, palladium, palladium production, facts about palladium

Palladium - definition

Palladium is extremely heavy and very refractory, ductile and malleable, which is very easily rolled into foil and drawn into thin wire. In terms of its density, which is 12 g/cm3, palladium is still closer to silver, whose density is 10.5 g/cm3, than to its related platinum (21 g/cm3). Naturally occurring palladium consists of six stable isotopes: 102Pd (1.00%), 104Pd (11%), 105Pd (22%), 106Pd (27%), 108Pd (26%), and 110Pd (11%). The longest-lived and artificial radioactive isotope is 107Pd with a half-life of more than seven million years. Many isotopes of palladium are formed in small quantities by the fission of uranium and plutonium nuclei. In modern nuclear reactors, 1 ton of nuclear fuel with a burnup rate of 3% contains about 1.5 kilograms of palladium.

Palladium is

Palladium is one of the elements of the periodic table of chemistry. elements named after Mendeleev. In the table, this element has serial number 46 and is located in the fifth period elements.

Palladium is noble metals belonging to the platinum group. It itself has a white-silver color.

Palladium is the only chemical element with an extremely filled outer electron shell. There are 18 electrons in the outer orbit of the palladium atom.

Paladium is an element often used in the production of white gold or as the base of a palladium alloy. Even 1-2% palladium is enough to gold acquired a silvery-white hue. But most often it's white gold 583 samples contain 13% palladium. It is most suitable for setting diamonds.

Palladium is an element capable of enhancing the anti-corrosion properties of even one that is resistant to aggressive environments metal, How . The addition of palladium of only 1% increases resistance to sulfuric and hydrochloric acids.

Paladium is the material from which most medals awarded to outstanding scientists and athletes are made.

History of the discovery of palladium

Palladium was discovered by the English physician and chemist William Wollaston in 1803 while studying crude platinum, brought from the burning continent, in that part of it that is soluble in aqua regia. Having dissolved the ore, Wollaston neutralized the acid with a solution of NaOH, and then precipitated platinum from solution by the action of ammonium chloride NH4Cl (ammonium chloroplatinate precipitates). Then mercuric cyanide was added to the solution, which formed palladium cyanide. Pure palladium was isolated from cyanide by heating. Only a year later, Wollaston reported to the Royal Society that he had discovered palladium and another new noble metal, rhodium, in raw platinum. Wollaston derived the very name of the new element, palladium, from the name of the small planet Pallas, discovered shortly before (1801) by the German astronomer Olbers.

The forty-sixth element, due to a number of its remarkable physical and chemical properties, has found wide application in many areas of science and life. Thus, some types of laboratory glassware are made from palladium, as well as parts of equipment for separating hydrogen isotopes. Alloys of palladium with other metals find very valuable applications. For example, alloys of the forty-sixth element with silver used in communication equipment (making contacts). Temperature regulators and thermocouples use alloys of palladium with gold, platinum and rhodium. Certain palladium alloys are used in jewelry, dental practice (dentures), and are even used to make parts for pacemakers.

When applied to porcelain, asbestos and other supports, palladium serves as a catalyst for a number of redox reactions, which is widely used in the synthesis of a number of organic compounds. Palladium is used to purify hydrogen from traces of oxygen, as well as oxygen from traces of hydrogen. A solution of palladium chloride is an excellent indicator of the presence of carbon monoxide in the air. Palladium coatings are used on electrical contacts to prevent sparking and increase their corrosion resistance (palladizing).

In trade jewelry, palladium is used both as a component of alloys and on its own. In addition, the Russian Central Bank mints commemorative coins from palladium in very limited quantities. A small amount of palladium is used for medical purposes - the preparation of cytostatic drugs - in the form of complex compounds, similar to cis-platinum.

The honor of discovering palladium belongs to the Englishman William Hyde Wollaston, who isolated the new one from raw platinum in South American mines in 1803. Who is this man whose name is given to the pure palladium medal awarded annually by the Geological Society of London?

At the end of the eighteenth century, William Wollaston was one of many obscure London doctors practicing in poor working-class areas. A job that did not generate income could not suit an intelligent and enterprising young man. In those days, a doctor had to have the skills not only of a physician, but also of pharmacy, which in turn presupposed an excellent knowledge of chemistry. W.H. Wollaston turned out to be an excellent chemist - while studying platinum, he invented a new method for making platinum utensils and established its production. It is worth mentioning that in those years, platinum glassware for chemical laboratories was a necessity, because the excitement around scientific discoveries was the same as in the times of alchemists around the philosopher's stone. It is no coincidence that at the turn of the 18th and 19th centuries. About 20 new chemical elements have been discovered!

Indeed, the creation of new exchange-traded funds, which themselves have become active buyers of platinum, remains one of the main factors behind the significant increase in the price of platinum. Since both the properties and applications of palladium and platinum largely coincide, the markets for these metals are interconnected, which means we can expect a similar reaction of the palladium market to the activities of the funds.

Palladium is

Such assumptions are confirmed by Stuart Flerlage from the New York company NuWave Investment: “platinum prices are rising higher and higher... Perhaps we will see the same picture with palladium prices.” The creation of exchange-traded funds linked to the price of platinum could further spur demand for the metal, causing more manufacturers and jewelers to turn their attention to the still more affordable palladium, says Michael Gambardella, JP Morgan and Co. (JPM). “We expect the large price gap between the two metals to narrow,” adds Gambardella.

Sources and links

wikipedia.org - the largest free encyclopedia

helprf.com - Financial support center

interfax.ru - news portal

ru.goldsilvermetals.com - physical metals and their properties

i-think.ru - chemical reference book and metal trade

globfin.ru - global economics, finance and investments

xumuk.ru - chemical encyclopedia

forexpf.ru - site about online trading

ru.investing.com - the largest investment site

all-currency.ru - official foreign currency rates

alhimik.ru - site about chemicals

chemistry-chemists.com - magazine of chemist enthusiasts

Investor Encyclopedia. 2013 . - I, husband. Report: Palladievich, Palladievna and Palladievich, Palladievna. Derivatives: Paladya; Lada (Lada); Palya; Broadsword; Pasha.Origin: (Greek: Palladion palladium (image of Pallas Athena, according to legend, fell from the sky as a guarantee of her integrity... Dictionary of personal names

PALLADIUM- (Greek). A metal similar to silver is found in platinum ore and is used in the manufacture of astronomical and physical instruments. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. Noble PALLADIUM... ... Dictionary of foreign words of the Russian language

PALLADIUM- (Palladium), Pd, chemical element of group VIII of the periodic system, atomic number 46, atomic mass 106.42; refers to platinum metals, melting point 1554 shC. Palladium and its alloys are used to make medical instruments, dentures, crucibles for... ... Modern encyclopedia

I. Palladium, Palladios, c. 363,425 n. BC, Greek Christian historian and hagiographer. Born in Galatia. After completing his studies in 386, he became a monk, first in Palestine, then in Egypt, from where he made numerous trips to... ... Ancient writers

The metal is silver-white, ductile and malleable, easily rolled into foil and pulled into thin wiring. Palladium density 12.2; melting point 1552 degrees. WITH; Mohs hardness 5. In air at normal temperature, palladium ... Official terminology

- (Palladium), Pd, chemical element of group VIII of the periodic system, atomic number 46, atomic mass 106.42; refers to platinum metals, melting point 1554 °C. Palladium and its alloys are used to make medical instruments, dentures, crucibles for... ... Illustrated Encyclopedic Dictionary

PALLADIUM- in Greek mythology, a small wooden statue of the goddess Athena. She was kidnapped by Odysseus and Diomedes. According to Virgil’s Aeneid, genuine palladium was taken to Italy by Aeneas after the fall of Troy... Big Encyclopedic Dictionary

PALLADIUM- (symbol Pd), a silvery-white TRANSITION ELEMENT metal first discovered in 1803. Malleable, workable palladium is found in nickel ores. It belongs to the platinum metals and has chemical characteristics common to PLATINUM. Not … Scientific and technical encyclopedic dictionary

Small wooden statue of the goddess Athena. She was kidnapped from Troy by Odysseus and Diomedes. According to Virgil's Aeneid, genuine palladium was taken by Aeneas to Italy after the fall of Troy. (

What is palladium? It is a platinum group metal that has characteristic properties. Today it is considered one of the most expensive and sought after. It is used in various industries, but most often in mechanical engineering.

Palladium - No. 46 on the periodic table

How is it obtained in nature?

Pd rarely occurs in nature in its pure form, mostly in combination with other metals such as platinum, gold, silver and copper. It is difficult to find palladium in the form of nuggets, but it is possible.

Metal mining occurs in two ways:

1. In primary deposits.
2. In placer deposits.

In primary deposits, palladium is mined as an accompanying material in the processing of copper and nickel ores.

At alluvial deposits, metal is mined in the form of nuggets, where it accumulates for many years. Nuggets are found mainly in ore mining areas.

Natural nugget of palladium

As a percentage:

• nuggets make up 2% of the total production;
• the remaining 98% of the metal is mined during the development of primary deposits.

It is worth noting that Pd mining is also carried out on the territory of our country. There is one of the largest deposits in the Urals, however, its resources are almost exhausted. In Russia, metal is mined in the Far Eastern regions.

Pd mining occurs in the following countries:

1. Canada.
2. Austria.
3. Colombia.

In Russia, Norilsk Nickel is engaged in metal mining, extracting precious metal during the extraction of the main materials of its production - nickel and copper.

Properties

The properties of Pd allow it to be used in many industries. Palladium differs from other metals:

• chemical inertness;
• low density.

It has an external resemblance to silver.

The melting point of palladium is 1555 °C. Due to its malleability and plasticity, the metal is used to make jewelry.

But in its pure form, palladium is classified as a brittle, weak metal; it lends itself well to processing, but jewelry made from this material will not be durable. The product can be damaged using weak mechanical force.

For this reason, palladium is used in jewelry by creating a ligature. That is, other metals are added to the alloy to make jewelry.

Chemical properties:

1. Does not oxidize in nature.
2. Does not react.
3. Forms compounds with other chemical elements.

The properties of Pd indicate that it is an inert metal that does not oxidize when exposed to natural factors, as do all platinum group metals.

Palladium does not react with other metals, but dissolves in a mixture of sulfuric and nitric acids, which chemists call “aqua regia.”

Pd forms compounds with boron, chlorine, silicon and sulfur.

The properties of the metal are valued in the manufacture of jewelry. Jewelry made from palladium and alloys of other metals are wear-resistant, they are not susceptible to environmental factors and retain their shine and color for a long time. Plaque forms slowly on their surface.

A palladium bracelet or watch will last longer than others; white gold earrings or a ring will delight you not only with its beauty, but also with its resistance to chemicals and humidity.

The properties of Pd are valued not only by jewelers and motorists, but also by chemists and doctors who actively use the metal for various purposes.

In industry

Externally, the metal has a certain resemblance to silver in color. Due to its inertness and other qualities, palladium is used in the following industries:

• production of catalysts for cars;
• jewelry;
• medicine;
• investment;
• electronic;
• chemical

The use of palladium in the production of catalysts is a necessary condition for the production of a car of any brand. Necessary for afterburning exhaust gases. Interest in this metal is due not only to the desire of citizens to have a car, but also to EU standards. Pd helps reduce the amount of exhaust gases, so the popularity of the metal is steadily growing.

Palladium ingot from the Krastsvetmet plant in Krasnoyarsk

Jewelry made from Pd and other precious metals is always in demand. But the jewelry industry does not affect global production volumes due to the fact that it is almost impossible to find products made from pure metal. Palladium is added to the ligature used to make watches, cufflinks and other accessories. In addition, commemorative coins are minted from the ligature to the delight of numismatists.

In medicine, metal is used to make parts for pacemakers, as well as special utensils and instruments.

Investment is the purchase of Pd in ​​the form of bullion. You can also open a bank account, but the depositor will not see the bullion. But if you buy them directly, you will be able to hold palladium in your hands. Such investment of money brings investment only in the long term.

In electronics, Pd has found its application in the production of military and aerospace equipment. And also to create a special coating that protects parts from the effects of negative environmental factors and prevents oxidation. The metal is part of ceramic capacitors that are used to make motherboards. Thus, small amounts of Pd are found in mobile phones, computers and other household appliances.

The chemical industry uses the 46th element of the periodic table to make dishes, various flasks and other containers. And also for the release of acetylene, ammonia, chlorine and other substances, for hydrogen purification.

The use of palladium for the purpose of hydrogen purification is not used in its pure form. To reduce the cost of industrial production, palladium is combined with nickel and other metals.

What is affining?

Palladium refining is the process of separating it from other metals. It is used in laboratory conditions, but often chemists and enterprising craftsmen are ready to carry out refining at home.

This is done because:

1. The element is used in a large number of chemical reactions.
2. You can turn it in and get a reward.

The cost of one gram of Pd ranges from 1000 rubles and above. Therefore, it is much easier to hand over a few grams of palladium than to collect parts from a computer and radio.

You can try to get Pd in ​​two ways:

• electrolysis;
• dissolving in aqua regia.

If you try to remove Pd from parts by electrolysis, then you cannot do without a mixture of sulfuric and nitric acids. Electrolysis is carried out in sulfuric acid concentrate; the main part of the copper and brass parts will not be damaged, it will remain. During the process, palladium itself is not formed; it will be possible to separate the alloy, which contains Pd. The resulting alloy must be dissolved in aqua regia.

How to identify palladium? It will come off the parts as a black powder or flakes. As long as the electrolyte is clean, washing is easy; if the solution is heated, then it needs to be cooled. The sludge is treated using aqua regia.

During operation, a voltage of 11–13 volts is required; it is supplied before the part is immersed in the solution. It is also necessary to consider the process of separating Pd from other elements, such as silver, gold, etc. For this you will need nitric and hydrochloric acids, as well as a solution of ammonia and water.

Nitric acid, along with sulfuric acid, helps separate Pd from other elements. You can understand that palladium is in a solution by simply assessing its color. During the reaction, the solution acquires a characteristic brown tint. This indicates that Pd is present in the alloy and it makes sense to continue the experiments.

If the alloy also contains gold, then the solution is left for a day, after filling it with cold water. Next, the silver chloride is filtered, resulting in only gold and Pd remaining in the solution.

The palladium refining procedure is carried out using ammonia. It is combined with the solution, the mixture is left for two days, after which the gold can be filtered out, and the palladium will remain in solution. In the future, gold can be restored using hydrochloric acid and zinc.

When adding hydrochloric acid to a solution with Pd, an orange or yellow precipitate appears. After a few hours, the precipitate should be filtered, dried and calcined at a temperature of at least 500 degrees. As a result of the procedure, Pd refining can be obtained. Some amount of the precious metal will remain in solution; it can be obtained through repeated refining.

The productivity of the process depends on how much palladium was contained in the parts, as well as on what elements other than Pd were included in the alloy.

In general, the procedure is quite complicated, requires certain skills in chemistry, and sometimes you can get a positive result only through trial and error.