Where can you find palladium. Independent examination Volgograd

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.

On the territory of Russia, 2 samples are legally approved - 500 and 850. Nickel, silver and copper act 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- a rare mineral, a noble metal of the platinum group, silver in color, not tarnished in air. Discovered by the English chemist and mineralogist W.H. Wollaston, who discovered palladium in native platinum in 1803. Malleable and malleable. More fusible compared to platinum, it is easily rolled and drawn into wire. Melting point 1552°C. Paramagnetic Soluble in HNO 3, hot concentrated H 2 SO 4 and aqua regia. Palladium has an extremely high affinity for hydrogen; in powder form it can absorb a volume of hydrogen 900 times greater than the metal’s own volume. Compared to other platinum metals, it is less resistant to oxidizing agents.

See also:

STRUCTURE

Palladium is a silver-white transition metal with a face-centered cubic lattice of the Cu type (a = 0.38902 nm; Z = 4; space group Fm3m). The unit cell of a face-centered cubic lattice is a cube with edge a. There are 8 atoms at the vertices of a cube. In addition, there is one atom at the center of each of the 6 faces.

PROPERTIES

Palladium is plastic; microadditives of nickel, cobalt, rhodium or ruthenium improve the mechanical properties of Pd and increase hardness.

Insoluble in water; density - 12.02 (20 °C, g/cm³); under special conditions it forms colloidal palladium and palladium black. Of all the platinum group metals, palladium is the most fusible. Melting point is 1554 °C (in some sources 1552 °C); boiling point about 2940 °C. Melting heat - 37.8 cal/g; specific heat capacity at 20 °C - 0.0586 cal/(g deg); electrical resistivity at 25 °C - 9.96 μOhm/cm; thermal conductivity - 0.161 cal/(cm·sec·deg). A paramagnetic material, that is, is magnetized in an external magnetic field in the direction of this field.

In its pure form, palladium has a beautiful silvery-white color. Like all noble metals, its color does not change over time.

Palladium in its pure form is a fairly soft metal. Its hardness is 373 MPa Brinell, which is approximately equal to the hardness of platinum (392 MPa) and exceeds the hardness of gold and silver (245 MPa). The hardness of pure palladium increases when cold worked by forging or rolling. During annealing, the hardness decreases again. Pure palladium cannot be used in jewelry; it will be extremely sensitive to mechanical stress. However, adding small amounts of other metals, especially nickel or ruthenium, to palladium significantly increases its hardness. For example, palladium 950 is used for the production of jewelry in Europe and North America, i.e. The jewelry contains 95% pure palladium. The remaining 5% is usually ruthenium or copper. In Russia, alloys of palladium with silver and nickel of 500 or 850 standard, and an alloy with copper of 850 standard are used to make jewelry. The wear resistance of palladium jewelry is approximately equal to that of platinum and is higher than that of gold and silver jewelry.

RESERVES AND PRODUCTION

Geologists have calculated that palladium accounts for 6% of the Earth's interior. That is, there is twice as much of this noble metal in the depths as gold. Palladium is isolated from platinum, which means it is mined in the same deposits.
These are located on the Kola Peninsula and the Urals. Deposits have recently been explored near Norilsk. The platinum of these deposits contains almost half of palladium.
Outside of Russia, the lands of Alaska, Australia, Colombia, Canada, and Africa are famous for the presence of valuable metal. The last two countries are rich in nickel ores. When processing them, palladium is also extracted. Therefore, it is Africa and Canada that lead in the production of this metal.
Supplies of palladium in the world in 2007 amounted to 267 tons (including Russia - 141 tons, South Africa - 86 tons, USA and Canada - 31 tons, other countries - 9 tons). Palladium consumption in 2007 was 107 tons in the automotive industry, 40 tons in the electronics industry, and 12 tons in the chemical industry.

Palladium is mainly obtained by processing sulfide ores of nickel, silver and copper.

ORIGIN

Palladium occurs as an impurity in many sulfides and silicates of ultramafic and mafic rocks. Some coals are enriched with palladium up to 10%; increased concentrations are observed in manganese ores, phosphorites, and plant ash. Palladium content is elevated in ultramafic rocks and rocks containing Cu, Ni and Te sulfides. Usually found in nature as an impurity in native platinum, with which it forms a disordered solid solution; sometimes found in its placers in the form of rounded grains. As a rule, it contains impurities of platinum, iridium, gold, and silver. Palladium platinum contains 19-40% palladium, palladium stannoplatinum -17-21%, polyxene - up to 6%, ferroplatinum - up to 13%, iridium platinum - up to 4%. It can also be found as an admixture to native gold (in Brazil, for example, a rare variety of native gold (porpecite) was found, containing 8-11% palladium). It is formed in the zone of oxidation of primary sources of platinum and directly in placers as a result of supergene transformation of platinum minerals. In iron meteorites, there is up to 7.7 grams of substance per ton. palladium, in stone - up to 3.5 g.
Since alluvial deposits of native palladium are very rare, the main raw materials for its associated production are sulfide ores of nickel and copper (Norilsk region, etc.)

APPLICATION

Palladium is often used as a catalyst, mainly in the hydrogenation of fats and cracking of petroleum. Palladium chloride is used as a catalyst and for the detection of trace amounts of carbon monoxide in air or gas mixtures.

Palladium chloride is used in electroplating 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.

Palladium and palladium alloys are used in electronics - for coatings that are resistant to sulfides (an advantage over silver).
In particular, palladium is constantly consumed for the production of high-precision precision resistance rheochords (military and aerospace technology), including in the form of an alloy with tungsten (for example, PdV-20M). The use in these units is due to the high wear resistance of palladium, which is ideal for its use in contact groups. By the way, rheochords made of palladium wire were widely used in civil equipment, and palladium in its pure form was used in the contacts of stepper switches of control-recording machines, in the contacts and strings of MKS (multiple coordinate connectors) of ATSC (automatic telephone exchanges coordinate) produced with 1982 to 1987 USSR.
Palladium is also included in ceramic capacitors (type KM), with high temperature stability of the capacitance in high-frequency equipment for radio broadcasting, radio communications, and television.

In alloys used in jewelry (for example, to produce a gold-palladium alloy - the so-called “white gold”). Palladium, even in a small concentration in the alloy (about 1%), changes the color of the gold-based alloy from yellow to silver-white. The main palladium-silver alloys used in jewelry have silver grades of 500 and 850 (as they are the most technologically advanced for machining and are decorative). Commemorative coins are sometimes minted from palladium in limited editions.

Medical instruments, parts of pacemakers, and dentures are made from palladium and its alloys;
In some countries, a small amount of palladium is used to obtain cytostatic drugs - in the form of complex compounds, similar to cis-platinum.

Palladium - Pd

CLASSIFICATION

Strunz (8th edition) 1/A.14-20
Nickel-Strunz (10th edition) 1.AF.10
Dana (7th edition) 1.2.1.4
Dana (8th edition) 1.2.1.4
Hey's CIM Ref 1.66

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 an 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.

When most people hear the phrase “precious metals,” they immediately think of gold, platinum, and the like. Few people remember other representatives of this group. One of these undeservedly forgotten noble metals is the element palladium. Despite its popularity, which is significantly inferior to its “brothers”, it is used in many industries and has very interesting properties.

History of discovery and name

The title of discoverer of palladium belongs to William Hyde Wollaston. In 1803, this English chemist managed to isolate a new element from South American platinum ore. The experiment during which Wollaston obtained palladium consisted of several stages:

The chemist named the discovered element in honor of Pallas, an asteroid discovered by a German astronomer a year before Wollaston’s discovery. The asteroid, in turn, received its name from the ancient Greek goddess Pallas Athena.

According to legend, an image of the goddess, called a palladium, fell from the sky. Once within the walls of Troy, this talisman made it indestructible. But after the palladium amulet was stolen, the great kingdom fell.

Characteristics and properties

In the periodic table, palladium is number 46 in the tenth group (vertically) between nickel and platinum and in the fifth period (horizontally) between rhodium and silver. The accepted designation for this noble metal is Pd, derived from the Latin name Palladium.

Physical parameters

This rare element belongs to the transition metals and at the same time belongs to the platinum group of metals, also called light platinoids. It is known what palladium looks like in the form of a simple substance - under normal conditions these are silvery-white and very heavy crystals, characterized by:

  • viscosity;
  • malleability;
  • softness;
  • plasticity.

The crystal lattice of pure matter is a cubic system with a face-centered structure of the copper type. The following have the ability to improve the mechanical characteristics of palladium:

  • cobalt;
  • nickel;
  • rhodium;
  • ruthenium.

In particular, microadditives of these elements significantly increase the hardness of the substance. Among the physical features, the density of palladium should be noted - under normal conditions it is 12 g/cm3. Judging by this indicator, the element is much closer to silver than to its “relative” platinum - the density of silver is 10.5 g/cm3, while that of platinum reaches 21 g/cm3.

As is known, the specific gravity of metals is equal to their density. Thus, in this indicator, the substance is closer to silver than to platinum. If, for comparison, we take the same jewelry made of palladium and platinum, the latter will be noticeably heavier.

Continuing the theme of weight, it is worth noting the molar (atomic) mass - it is 106.42 g/mol or daltons. The atomic radius is 137 picometers, and the covalent radius reaches 128 picometers.

Palladium is a unique substance. This is the only one of all existing chemical elements whose outer electron shell is filled to the limit or maximum. The outer orbit of an atom of this metal contains 18 electrons.

It is impossible to dissolve the substance in water. It is also characterized by considerable refractoriness - the melting point of palladium is 1554 degrees Celsius. The temperature required for boiling reaches 2940 C. When special conditions are created, a substance can transform:

  • into palladium niello;
  • into colloidal palladium.

This precious metal is paramagnetic as it has positive magnetic susceptibility. The electronegativity value on the Pauling scale is 2.20.

Chemical features

The title of platinum metal with the greatest chemical activity belongs to palladium. It does not react:

  • with water;
  • a solution of hydrogen nitride or ammonia;
  • dilute acids and alkalis.

But it is capable of reacting with hot concentrates of nitric and sulfuric acids, which distinguishes palladium from all other platinum group metals. At room temperature, the reaction of the substance starts:

  • with wet bromine and chlorine;
  • with royal vodka.

When fused with potassium hydrogen sulfate, palladium begins an oxidation process. Interaction with molten sodium peroxide is also possible. Heating is the main condition for the implementation of a chemical reaction with many elements, including:

  • silicon;
  • arsenic;
  • selenium;
  • sulfur;
  • tellurium;
  • fluorine.

When in contact with air during heating within the temperature range of 300-850 degrees, the light silver metal becomes dull, as an oxide film forms on its surface. At temperatures below 300 C, the metal remains stable; above 850 C, the previously formed film decomposes.

Isotopes and human exposure

Chemistry causes negative associations for many people, so it would be useful to focus on whether the metal has a harmful effect on humans or is safe.

A natural element created by nature is formed by six isotopes:

  • 106Pd (27.34%);
  • 108Pd (25.46%);
  • 105Pd (22.34%);
  • 110Pd (11.72%);
  • 104Pd (11.14%);
  • 102Pd (1%).

The isotopes are stable, so natural palladium is harmless. But there is also a variety created artificially. This is 107Pd - the longest-lived isotope of the element. It is radioactive and therefore dangerous. Its half-life exceeds seven million years.

The majority of isotopes are of natural origin. But quite a few of them are also formed in reactors during the fission process of plutonium and uranium nuclei. The formation of palladium in this way occurs gradually. Modern nuclear installations contain approximately 1.5 kg of palladium per 1 ton of nuclear fuel (assuming a 3% burnup).

Being in natural conditions

  • nugget (allopalladium);
  • intermetallic type minerals (stannopalladinite, palladinite platinum, etc.);
  • various compounds (braggite, palladinite, etc.).

There are about three dozen varieties of palladium minerals known to science. This element often acts as an accompaniment to other platinum metals. The content of the substance in the platinum mixture ranges from 25-60% (depending on the deposit).

Native palladium is extremely rare. In appearance it is almost indistinguishable from platinum. In addition to palladium, nuggets also contain other elements:

  • iridium;
  • gold;
  • platinum;
  • silver.

According to Goldschmidt's geochemical classification of elements, palladium (along with all other platinoids) is among the siderophiles. In other words, it has a characteristic affinity for iron and is concentrated in the earth's core.

Platinum and palladium are mined from two types of deposits:

  • alluvial;
  • indigenous

The difference between these varieties lies in the method of production. In bedrock deposits, the metal is contained in minerals. In such places, the extraction of the substance is carried out by processing ores - copper or nickel. Palladium is recovered as a by-product.

Placer deposits are former primary ore deposits. They have already been mined, the palladium has been released and taken the form of nuggets.

Alluvial deposits where palladium can be mined account for about 2% of global production. The largest of them are located in Russian regions - in the Urals and the Far East, as well as abroad:

  • in Australia;
  • Colombia;
  • Canada;

The predominant 98% of mined palladium is obtained from the depths of the earth in indigenous deposits. The main ores being mined are:

  • copper-nickel;
  • platinum;
  • chrome.

Russia and South Africa have the status of leading countries in terms of global production of precious metal from such deposits. In honorable first place is the Norilsk Nickel enterprise - it accounts for almost half of the world's production volume. And the Bushveld complex (South Africa) owns the largest reserves of platinum group metals in the world.

Processing of ores is the main method of obtaining palladium, but not the only one. The element is recovered from recycled materials. This production method accounts for approximately 10% of total world production.

Industries and applications

Due to its characteristic properties - both physical and chemical - the element palladium is widely used in the production of electronics and in the chemical industry. Belonging to precious metals led to the use of the substance as a material for jewelry.

It is worth noting that jewelry made from pure palladium cannot be found - they simply are not made. This metal is very soft - it can easily be pulled into thin wire or rolled into foil, but any metal product without impurities will not withstand even a light load. Therefore, even at the production stage, small proportions of other metals are added to the material.

In the widespread use of palladium, a key role was played by the fact that this element can be processed by any method and used in a wide variety of forms, types, etc. To visually assess the scale of use of the metal, it is worth dividing the areas by percentage:

  • 70% - automotive industry;
  • 10% - electronics production;
  • 5% (for each) - chemical industry, medicine, investment;
  • 5% (in total) - jewelry, coin making, etc.

Recently, the use of palladium as an investment object has been gaining popularity. The value of this precious metal is very high; it is involved in exchange trading, so such an investment of funds can be quite profitable.

However, not every owner of palladium brings happiness. For the acquisition, storage and sale of an illegal nature, the prescribed criminal punishment will necessarily follow - imprisonment for a maximum of 5 years.

In 2015, FSB officers detained an Omsk resident in whose garage 1.5 kg of catalysts containing palladium worth 2 million rubles were stored. Where and how the lawbreaker managed to get such a quantity of palladium catalysts is unknown, but this interesting fact from the modern history of palladium proves that the desire to gain profit through illegal means will sooner or later backfire.

The so-called - platinoids.

There is a rather interesting story associated with the discovery of this metal. In 1803, one of the major British mineral traders received a small ingot of palladium in an anonymous letter offering to sell it. Fierce discussions flared up around the new (as stated in the letter) metal - a relative of platinum. Conservative British scientists called the new substance a “pseudo-metal,” most likely an alloy of mercury and platinum. However, other scientists found no trace of mercury or platinum. A little later, when the controversy had subsided, an advertisement was published in one of the scientific journals promising a considerable reward to anyone who could repeat this fusion. Discussions flared up with renewed vigor, but any attempts to recreate the material turned out to be a natural failure.

Finally, in 1804, British scientist William Wollaston appeared on the scientific scene with another palladium ingot. The year before, he managed to isolate palladium from platinum ore using a mixture of nitric and hydrochloric acids (“aqua regia,” which dissolves gold and platinum).

The new metal, in addition to its beautiful appearance, did not tarnish or oxidize, which was ensured by 18 electrons in its outer orbit. At the same time, it was flexible, malleable and soft. The addition of a small part of other platinoids, gold or silver gave it strength.

The metal received its name in honor of the recently discovered (1802) asteroid Pallas, named, in turn, in honor of the ancient Greek goddess Pallas Athena. Simultaneously, by the way, with the discovery of palladium, from the same platinum ore, Wollaston discovered another platinum - rhodium.

Application of palladium.

Applications of palladium received in a wide variety of production areas:

  • in dentistry in the production of dental crowns and dentures;
  • in the chemical industry (production of chemical glassware);
  • in medicine - in the production (due to bactericidal properties) of medical glassware, instruments and even pacemakers;
  • in pharmaceuticals (a small amount of palladium is included in some medicines);
  • in electronics and electrical engineering in the production of printed circuit boards and electronic microcircuits;
  • in the jewelry industry (alloys of palladium with platinum or gold are quite popular; the latter, when combined, turns into “white gold”, more durable and practical);
  • in the glass industry (glass melting);
  • in the automotive industry (due to the fact that palladium is a strong catalyst, it is used in technology for purifying automobile exhaust gases);
  • in aircraft and rocket production (again, due to its catalytic properties, palladium is used to purify hydrogen).

Palladium mining and market.

Key areas palladium mining in the world are:

  • Russia (near Norilsk);
  • South Africa;
  • Alaska (USA);
  • Canada;
  • Australia.

About half of the world palladium export falls on the Russian Federation. South Africa is in second place, followed by Canada and the United States.

The main consumers of palladium are enterprises in the electronics, chemical and automotive industries. By volume palladium import China occupies a confident first place in the world.

Palladium, having similar physical and chemical properties to platinum, is about half the price, so it continues to be in demand in the metals market, including London Metal Exchange (LME).

Peak world palladium supplies falls on the 1990s and 2000s, which is explained by the increased attention of some states to the environmental safety of automobile engines.

Palladium price dynamics.

Palladium price increased in the 70s of the last century, when it began to be used in the automobile industry as an exhaust gas converter instead of platinum, since the latter was almost twice as expensive. However, the level of palladium production was then not high enough for the global automotive industry. Therefore, the peak of palladium sales occurred in the 90s, when new deposits of this metal were developed.

In the early 90s, the price of palladium on the London Stock Exchange fluctuated around $150-200 per troy ounce (about 31 grams). It should not be forgotten that, taking into account inflation, 150 dollars in 1990 was equivalent to approximately 600 dollars in 2010.

Palladium price dynamics intensified in the early 2000s, and in 2001 the price of palladium reached a historical record, when this noble metal began to cost about 900-1000 dollars. A new increase in palladium prices occurred already in 2011, when it amounted to $825 per troy ounce. In subsequent years, the price of palladium stabilized at $700-800 per ounce.

However, in the last two years there has been a gradual decline on the stock exchange. palladium futures. Considering the decline in metal production and its potential shortage, this seems somewhat paradoxical, since a decrease in production usually causes an increase in price. Experts attribute this situation to the decline in the economy of China (the main importer), as well as the emergence of cheaper exhaust gas neutralizers in the automotive industry.

In 2015, the average world price for palladium dropped to $550-600 per ounce, and the decline continued.

However, precious metals exchange experts believe that investment in palladium are not nearly as hopeless as they seem. Palladium Price Forecasts in 2016 they are much more optimistic. Firstly, the need for palladium in electronics, medicine, chemical and other industries has not been canceled. Secondly, Russia has plans to develop new, not yet touched upon, palladium deposits.

Anyway, investing in palladium, like any other precious metal, will not bring quick profit. They are more suitable for long-term investment, that is, saving money.

Regarding the role of palladium in the automotive industry, new catalytic converters based on organic carbamide (urea) are used more with diesel rather than gasoline engines. Therefore, palladium-based catalysts still have a fairly high prospect of application (especially considering that many manufacturers still use expensive platinum-iridium alloys).