Application of platinum. Where and how is platinum used?

Platinum, a noble metal of gray-steel color, is one of the “three” in demand along with gold and silver. Now platinum is an even more sought-after metal than the other two, and not just in the jewelry industry. Heavy and soft platinum is widely used in jewelry and dentistry, medicine, the manufacture of mirrors for laser technology, resistance elements, and it is also used for the manufacture of coins.

Platinum compounds and elements can be found in LCD displays, in the mechanism of heavy-duty vehicles, in catalysts for oil refining and much more. And just a few hundred years ago, platinum was a cheap metal that people tried to get rid of without hesitating to drown it in the sea. This attitude towards the metal, the name of which is even translated disparagingly as “little silver,” is due to the fact that Spanish counterfeiters very quickly began to use it to make fake coins. The King of Spain was forced to ban the import of platinum into the territory of the metal that had just been discovered by Old Europe, which was mined in America by the Incas.

Now, of course, the situation has changed: platinum is very expensive, it is used very widely, and there have long been five countries in the world in which this metal is mined.

The total in the world is standardly called platinum: South Africa, Russia, Zimbabwe, Canada and the USA.

Canada, about 5 tons, 2011 - 5th place

The North American Palladium company and the Sudbury Vale company from Canada offered about 6 tons of platinum to the world market. Last year was a year of growth for NAP, when it was able to process 1.7 tons of non-ferrous metal ore, but for Val the time was not very successful. The Canadian company Sudbury Vale sharply lost its position in 2011. From almost 3 tons, the supply of platinum fell to 1.7 tons. Indicators for palladium also collapsed. The most common reason cited was the death of one of the workers at the mine in Sudbury, which led to a shutdown of production.

The Stillwater Mining Co monopoly is now the only company that deals specifically with platinum group metals, having made them its main supply product. The company owns two mines in Montana, Stillwater and East Bouder, where most of the platinum is mined. In 2011, mines produced 7% more platinum than in the same period last year. The company is continually investing in the Graham Creek project to gain access to additional resources and expects to complete it within a few years. The Alaska company XS Platinum, on the contrary, lost its position. She works with deposits of precious metal that are more than half a century old, which suggests that their resource has greatly depleted itself.

Zimbabwe, which ranks 3rd in the list of top 5 platinum mining, is one of the most promising territories for the development and further production of platinum group metals. It represented almost half of the production volume of all other countries except Russia and South Africa, where the largest amount of platinum is mined. The internationally respected company Johnson Matthey, through its manager Mark Danks, stated that it sees a profitable project in Zimbabwe. This became especially obvious after the formation of a joint Russian-Zimbabwean platinum mining enterprise, Ruschrome Mining, which has now actively begun work at a deposit of the precious metal called Darwendale.

The RusChrom company/ has begun open-pit mining at the Darwendale platinum deposit in Zimbabwe. The company has grandiose plans: by 2014, Ruschrome Mining is going to begin mining marketable ore, which will be processed domestically, and in 2015, construction of an ore enrichment plant will begin. In any case, Johnson Matthey forecast platinum production in Zimbabwe at 11.5 tons in 2012, which would be an increase of 6-7% compared to the same period last year.

In 2011, Russia was able to offer 26 tons of metal to the world market, which is the second largest in the world. Of course, South Africa, where the most platinum is mined, Russian Federation will not catch up for objective reasons, but she is in second place in the world rankings, and has no intention of losing her position. Platinum mining dates back 200 years. The noble metal was first discovered in the Urals, not far from Yekaterinburg, although it had been known in production among jewelers and coin makers for a long time.

This happened in 1819, and in 1824 platinum was found near Nizhny Tagil. Currently, the developed reserves in the copper-nickel ore complex are distributed in the Norilsk ore region of Russia as follows:

• Oktyabrskoe;
• Talnakhskoe;
• Norilsk-1;

The only deposit of platinum low-sulfide ores is MS-Gorizont. Russia uses platinum not only for domestic consumption, but also supplies it to a variety of industries in China, Japan and Europe.

The country where the most platinum is mined, the absolute leader, whose shipments and deliveries to the world market increased by 7% due to the release of platinum from current production and warehouse stocks that entered the world market. But, nevertheless, primary production decreased by 3%, which amounted to more than 3.5 tons. This is due to several reasons, which relate not only to the technology itself and the organization of the metal mining process, but also to the “human factor,” which only aggravated the situation. Last year's summer was marred by a three-week strike at Lonmin's Kari mine.

This event, multiplied by the total production costs, led to such unpleasant results. South Africa is dominated by several companies that develop and mine platinum: Anglo Platinum; Impala Platinum; Lonmin, with its mines in the Western Bushveld, is now the best known. Unfortunately, February 2012 showed a decline in the level of platinum production in South Africa when compared to the same period in previous years.

This is due to the wave of strikes that swept through the mines of almost all manufacturers. At the same time, the market has retained its viability, the issue of strikes has ceased to be so pressing: one can hope that South Africa will not fall out of the global list of TOP 5 platinum mining countries.

The most underrated of the three known to everyone noble metals - platinum. There is nothing surprising in this: a platinum nugget is black and unsightly, and anyone who finds it will step over it and move on.

In ores, platinum and gold often accompany each other. However, gold miners of the past, when smelting gold, simply threw away pieces of nondescript metal. Platinum did not melt together with gold and silver; under the hammer on the anvil it became harder; in appearance it slightly resembled silver - but dirty, worthless...

In a word, the unnecessary impurity went to waste. And there was very little of it! So little that European precious metal foundries even talk about the existence of platinum as individual element The universe was not realized until the middle of the 19th century. Unlike the Incas...

The Precious Metal's Tangled History

Modern scientists know about the origin of platinum and platinum group metals from spectrographic observations of large-scale space disasters. Heavy metals, including silver, gold, platinum and platinoids - , and , - appear in interstellar space as a result of fusion reactions accompanying supernova explosions and collisions of massive old stars.

The dispersed star substance condenses into dust. Gravitational fluctuations form more or less massive clumps of matter. In different ways, interstellar matter, some of which consists of noble metals, reaches the surface of the planets. Where it disperses in the thickness of the crust...

The processes of erosive destruction of the planet's bedrock with the reformation of sedimentary and metamorphic layers allow heavy metals to concentrate in deposits. Rare and few in number – if we talk about platinum and platinum group metals.

Platinum and platinum group metals on Earth

There is little platinum in the earth's crust. Just 0.0000005% (five ten-millionths of a percent) of the mass of the Earth. This does not prevent industrialists interested in platinum from extracting 200 tons of the precious metal annually.

Explored reserves of platinum are estimated at 80 thousand tons, with the main deposits located on the territory of five states. South Africa and Zimbabwe, Russia and China, the USA concentrate approximately nine-tenths of the world's platinum reserves. Canada, South America and other countries have small deposits.

However, there are estimates that allow 90% of raw platinum to be attributed to South African mines. Which, of course, indicates not so much the exclusivity of southern Africa as the insufficiency of geological exploration of the subsoil of the rest of the Earth.

Natural platinum compounds

Pure platinum is rarely found in nature. Native platinum is, as a rule, a mixture of several metals with a predominance of platinum itself. The most typical of the compounds are defined as minerals.
Polyxene contains from 80 to 88% platinum and about 10% iron. Cuproplatinum, in addition to the noble metal, contains up to 14% copper and approximately the same amount of iron. Nickel platinum (found in vein deposits mixed with iron, copper and nickel) is well known.

It happens that platinum combines with sulfur (the mineral cooperite), and with arsenic (sperrylite), and with antimony. However, much more often natural platinum is found in combination with palladium or iridium. The remaining platinum group metals are present in ores in small, usually, concentrations.

No particularly large platinum nuggets have been found in nature. Not very impressive in appearance, platinum nuggets weighing 5918 g and 7860 are stored in the Diamond Background of Russia. They were found at the Konder (Khabarovsk Territory) and Isovsky mine (Ural) placer deposits.

History of the development of wealth

Found in placers since ancient times, platinum was of no interest to Europeans. The most practical thing was done by the peoples of northern Asia, who used platinum grain as shot or buckshot. However, the South American Inca and Chibcha tribes, who mined a lot of gold and silver in the Andes, treated platinum with great reverence. Not knowing how to properly process the refractory metal, they kept platinum as a gift from the gods and used it in cult rituals.

The Spaniards, who contemptuously called their new metal “silver,” figured out how to falsify gold using platinum. It is very profitable to take platinum at a bargain price (half the price of silver) and add it to a gold alloy. When mixed with gold in relatively small quantities, platinum does not change the color of the alloy. But it allows you to save expensive material!

That is why the Spanish authorities ordered the platinum to be sunk: partly right in Colombia, partly already in Spain. And they drowned it until the Madrid court itself decided to make money by counterfeiting. Looking at the tricks of those in power, natural scientists became interested in the new metal, and after conducting a series of research experiments, first in 1750, and again as early as 1803, they isolated pure platinum from scattered samples.

It took another 30 years for Julius Scaliger, a chemist from Italy, to provide irrefutable evidence: platinum is a chemical element, and not dirty gold or silver spoiled by impurities. However, Scaliger had predecessors who claimed the same thing 80 years before him - but the science of those years was not very fast. In fact, recognition of platinum came only in the 19th century.

The English engineer William Wollaston (who discovered rhodium and palladium) proposed making vessels from platinum for the production of concentrated acids. The offer turned out to be reasonable, and the demand for metal increased.

Russia, which at that time possessed relatively rich deposits of platinum, began minting coins from it ten years after the start of mining the precious metal. There was no practical use for the precious metal in Russia for a long time, and all supplies (more than 16 tons of purified platinum) were sold to England in 1867.

As happened before and later, and not only with Russian rulers, they simply did not consider the potential of their “bird in hand”.

Physicochemical properties of platinum

By appearance platinum resembles silver, but is darker and dimmer. The color of platinum is characterized as grayish-white; in compounds, the purity of the color decreases. The melting point is high: 1768.3°C. Hardness does not exceed three and a half Mohs units. The crystal structure of platinum is cubic. In nature, platinum crystals are found in vein deposits and nuggets.

Platinum is chemically stable, but reacts with hot aqua regia. Dissolves in bromine. When heated, it reacts with a few metals and non-metals. Dissolves molecular hydrogen. Known as an active catalyst for the oxidation and addition of hydrogen. In particular, spongy platinum can provoke the combustion of a mixture of hydrogen and oxygen at low gas temperatures. Before the invention of matches, lighters using this principle were widely produced.

Application of platinum

In modern conditions, the demand for platinum is growing, and its use is intensifying. Until the middle of the last century, at least half of the mined platinum was consumed by jewelers, and a few more percent by dentists and doctors.
Jewelry platinum (especially treated with rhodium) is an excellent material for creating settings for colorless and white stones, pearls, topazes, and semi-precious stones with subtle colors.

Until recently, Japan remained the main consumer of platinum jewelry (now it has been replaced by China): platinum rings there are as common as gold jewelry. Up to 25 tons are sold annually in China jewelry, made of platinum.

An increase in demand for jewelry platinum and platinum group metals is also observed in Europe. However, platinum jewelry is unpopular in Russia: only 0.1% of the global volume of platinum jewelry is sold here.

The lion's share (at least 90%) of the mined metal goes into industry. Platinum is used to make devices for the chemical industry: laboratory glassware and equipment, filters, electrodes. At least half of technical platinum is used for the production of all kinds of catalysts, including automobile ones.

Electrical engineering and glass production cannot do without platinum. Platinum or platinized contacts are not afraid of arcs. Platinum dies are used to produce fiberglass.

Without the stability of platinum as an electrically conductive, corrosion- and heat-resistant material, the space industry would be unlikely to reach its current heights. One of the mass standards is made of an alloy of platinum and iridium: it is a cylinder 39 millimeters high and also 39 millimeters in diameter.

Platinum is also used as a banking metal: the cost of platinum is consistently high, the price increase is constant; As an investment object, this noble metal is very profitable!

Having no use in the past, today platinum is in demand more than ever. And if humanity either wants or doesn’t want to send space tractors for hypothetical golden asteroids, then celestial body The expedition will be equipped with platinum without hesitation: the unique properties of the noble metal are so useful.

The photo shows artificially grown platinum crystals from the gas phase, with smooth edges and a few centimeters in size.

Classic laboratory glassware made of noble platinum

Platinum is a weakly reactive, refractory and corrosion-resistant metal. Chemical laboratory glassware or so-called platinum crucibles are made from platinum metal, intended for heating acid melts or solutions in them. For example, platinum crucibles are resistant to sulfuric acid or its acid salts. But melts of alkalis, especially in the presence of oxidizing agents, cause corrosion of platinum, so it is better to heat alkali metal hydroxides not in platinum dishes, but in silver ones.

The photo below shows an example of a classic small platinum crucible. Large crucibles are used for melting special glass and growing semiconductor single crystals.

Platinum coin

Today, coins made from platinum are issued for investment and collection purposes. The photo below is an image of an old, extremely rare and expensive platinum coin with a face value of 12 rubles, made in Russia in 1832. The platinum coin is in excellent condition, well polished and retains its attractive shine. The high value of this coin is due to its historical value, precious metal, from which this platinum coin was minted, is in good condition and of great weight.

What is a platinum bar?

The photo below shows two measured platinum bars, 999 fine and weighing 10 and 50 grams. Such measured platinum bars can be purchased at Russian Banks.

Platinum bars can be an excellent investment for free funds to protect your savings from possible inflation. In addition to being a profitable investment, platinum bars can be both collectibles and simply valuable gifts.

On the front side of platinum bars, there is a clear and legible marking. The imprints of the inscriptions on the ingots may be depressed or convex, depending on the manufacturing technology of the ingots. A platinum bar, on the front side, is marked with the following inscriptions: the inscription of the country of origin - “Russia” enclosed in an oval, below are the masses of the bars in grams: 10 and 50 grams, the name of the metal - “platinum”, the weight fraction of the precious metal in the bars - 999, 5 or its metric 999 standard, the manufacturer’s trademark, at the very bottom is the bar number (for platinum bars weighing 50 grams or less, the number can be printed on the reverse side).

Platinum engagement ring

Platinum is the strongest inert, noble and very beautiful metal. Its properties are used by jewelers to create jewelry. Platinum got its name from the Spanish conquistadors, who discovered this metal in the mid-16th century in South America (today this is the territory of the modern state of Colombia).

Initially, platinum had no practical value. People did not know the properties of this metal. They did not know how to melt platinum because they did not know its melting point. The metal was difficult to melt down. Platinum was valued at half the price of mined silver.

Today, the properties of platinum are appreciated according to its merits. Platinum is the most expensive precious metal. Jewelry made from platinum looks very beautiful and attractive.

The photo below shows a platinum engagement ring, high carat and well polished to a shine. If you take one each: silver, gold and platinum ring, identical in volume, then in your hands you can feel a clear difference in their weight. A platinum ring will naturally be heavier.

Platinum watch - chronograph

The photo shows a men's platinum watch. They are a classic and popular chronograph, with a built-in Swiss movement - ETA 7750. Platinum watches have a mechanical automatic winding. This chronograph is a Russian brand, from the Platinor company. The watch case is made of 950 platinum and is edged with diamonds. And the strap of the platinum watch is made of 850 palladium. The watch has a classic look and does not contain anything superfluous in its design. The glass of such watches is sapphire, which means that there will be no scratches on such glass. Although such sapphire crystals break easily. Therefore, the watch should not be dropped or struck. Platinum watches are protected from moisture and water. Having put the watch on your hand, you can swim in the water, wash your hands or dishes. However, you cannot switch the watch's chronometer buttons underwater.

Platinum and palladium are metals belonging to the platinum group of noble metals. They are considered rare in the land of metal. They have high density and viscosity. In order to process platinum and palladium, a very high level of professionalism is required. Platinum is a very hard metal and is difficult to machine. In order to make a platinum watch case, you will need more than one grinding wheel, since polishing wheels often wear out during polishing.

Platinum is an expensive precious metal compared to other precious metals. Therefore, its high cost is noticeably reflected in the price of platinum watches.

Palladium is a noble metal from the group of platinum elements, it is valued cheaper than gold, but in jewelry it is more expensive than gold metal, since it is a very difficult metal to work. In Russia, palladium jewelry is practically not made, since it is not profitable for the manufacturer to get involved with this metal. In Japan, palladium jewelry is extremely valuable and easily sold out.

Spongy platinum and platinum niello

Platinum is the strongest inert, chemically inactive metal and has catalytic ability. However, spongy platinum acquires completely different properties that are not characteristic of ordinary platinum.

Spongy platinum is a spongy mass gray, which is obtained by heating some platinum compounds. Platinum in such a spongy form has the ability to absorb various gases. This is explained by the fact that spongy platinum has a large surface area.

One volume of spongy platinum can hold several hundred volumes of oxygen. Such oxygenated spongy platinum has the ability to oxidize various substances (alcohol, sulfur dioxide, hydrogen, organic substances). Under normal room conditions, these substances are not able to combine with oxygen. And spongy platinum, having catalytic properties, promotes the oxidation of various substances with oxygen.

The oxidizing properties of sponge platinum are widely used in chemical laboratories and engineering. For example, the oxidizing abilities of spongy platinum are very clearly manifested when exposed to detonating gas (this is a mixture of hydrogen and oxygen). At first, the reaction is accompanied by the slow burning of hydrogen, and then when the spongy platinum becomes hot, an explosion occurs.

In its usual form, platinum has weak catalytic properties. A spiral wire over an extinguished wick of an alcohol burner will slowly smolder after the flame is blown out, as the alcohol vapor slowly oxidizes under the spiral.

In order for the catalytic reaction to proceed more intensely, both sponge platinum and platinum black are used. What is platinum black? Platinum black is a fine or fine powder of metal platinum, which is obtained by reducing its compounds and is used as a catalyst in various chemical reactions. Finely ground metal platinum itself does not enter into chemical reactions with various substances, but only facilitates the occurrence of certain chemical reactions.

The photo on the left shows sponge platinum, and on the right is platinum black.

White gold

White gold is an alloy of gold metal with other metals (silver, platinum, nickel, palladium), which color gold in white. If 585 standard gold is an alloy consisting of 585 parts by weight of pure gold and alloy metals: copper and silver, then the same 585 standard gold is an alloy containing 585 parts by weight of pure metal, only instead of copper, platinum or is added to the alloy, which colors the gold in white color. With a high content of silver in an alloy with gold, the alloy is painted in a matte white color.

The photo below shows two wedding rings, made of white gold alloy.

Platinum candles

The photo below shows automotive platinum spark plugs with platinum contacts. Platinum spark plugs, which perform the ignition function in internal combustion engines, received this name because refractory platinum is used in them to make electrodes. Platinum electrodes in spark plugs are good because they are highly resistant to corrosion and have high heat resistance. Platinum electrodes practically do not fade and can be used for a very long time. The platinum electrode allows the distance between the side and inner electrodes to remain unchanged for a very long period of time. An important characteristic of platinum spark plugs is the size of the gap between the inner and side electrodes, since the efficiency of ignition of the gas mixture in the engine cylinder depends on this. The high resistance of platinum to erosion makes it possible to increase the replacement interval to 90,000 kilometers.

Physical properties of platinum

The chemical symbol for platinum is Pt.

Platinum is a simple chemical element.

The atomic number of platinum is 78.

Platinum is a chemical element of the tenth group and the sixth period in the periodic system of D.I. Mendeleev, and is a simple chemical substance.

Atomic mass - 195.084 amu.

The electron configuration is 4f14 5d9 6s1.

Platinum is a heavy but soft metal.

Platinum is superior in hardness to gold.

Density of platinum under normal conditions: 21.09 – 21.45 g/cm3.

The boiling point of platinum is 3825 degrees.

The melting point of platinum is 1768.3 degrees.

Platinum was discovered in 1735.

The discoverer of platinum is considered to be Antonio de Ulloa.

The Spanish navigator and mathematician, Antonio de Ulloa, in 1748 brought from Peru the platinum nuggets he found there.

Pure platinum was first obtained from platinum ore in 1803 by the English chemist William Wollaston.

Platinum as an independent chemical element was discovered by the Italian chemist Gilius Scaliger in 1835, when the indecomposability of platinum was established.

Platinum belongs to the group of transition metals.

Platinum is a noble metal with a silvery-white color.

The white color of platinum is very similar to the silvery white color of silver.

The color of platinum can also be described as a metal that has a grayish steel color.

Platinum is a refractory and low-volatile metal.

Platinum has a face-centered cubic crystal lattice.

Platinum can be obtained in the form of platinum black, which has high dispersion properties. When heated, platinum is easily rolled and welded. Spongy platinum has a large surface area, so it adsorbs many gases well. Especially such adsorbed gases are: oxygen and hydrogen. The tendency of platinum to adsorb manifests itself not only when platinum is in a finely dispersed state, but also in a colloidal solution. Platinum, presented in the form of platinum black, in one volume can dissolve up to 100 volumes of oxygen. The property of platinum black to adsorb (dissolve) gases is used to accelerate chemical reactions. Therefore, platinum black is used as a catalyst in chemical reactions of oxidation and hydrogenation.

Even when heated strongly, platinum does not oxidize in air, and after cooling it retains the silvery-white color characteristic of this metal.

Despite its naturally hard properties, platinum can still be processed well. It is easily rolled, forged, stamped and lends itself well to drawing. If you roll platinum very hard into the thinnest sheet, you can get platinum with a thickness of 0.0025 millimeters.

Platinum is the strongest inert metal. Its inert properties in comparison with gold and silver, as well as with other inert metals, are much higher. Chemically, platinum is a weakly reactive metal.

Platinum, like silver, is a highly malleable and ductile metal. These are processed very well, drawn into fine wire and rolled into thin sheets. Compared to silver and gold, platinum is a more refractory metal.

Platinum alloys are usually two-component alloys, which are a solid solution of platinum with other alloying elements. The most important platinum alloys are the chemical elements - metals of the eighth group of the periodic system: Rh, lr, Pd, Ru, Ni and Co, as well as Cu, W, Mo.

Platinum alloys have a high melting point, corrosion resistance to aggressive environments, they resist oxidation even at high temperatures, and also have high mechanical properties and wear resistance. Some platinum alloys have catalytic properties in reactions: isometry, hydrogenation and oxidation. Platinum alloys lend themselves well to pressure treatment. Various products can be made from platinum alloys: stamping, rolling, forging and drawing.

Platinum is a rare, beautiful, inert, noble and precious metal, which in the periodic table of D.I. Mendeleev represents a group of metals - platinoids, similar in their properties.

Platinum is widely used in jewelry. Jewelry platinum as well as gold and silver, in pure form jewelers, as a rule, are not used. Jewelers in the manufacture of jewelry widely use platinum alloys, as they are the most mechanically stable. Platinum is often alloyed with palladium and silver. These alloy metals are added to platinum until the platinum alloy is suitable for making jewelry. Platinum alloys must have the necessary qualities: hardness, strength, fusibility, wear resistance, but at the same time they must remain easily processed alloys.

History of platinum

The word platinum was coined by the Spanish conquistadors, the discoverers of South America. When the pioneers first became acquainted with an unknown metal - platinum, they noticed that it looked very similar to silver. At that time the word patina in colloquial speech meant small silver or “silver”. This diminutive name was given to this metal because platinum was a useless metal and had refractory properties. People at that time did not yet know how to melt platinum and for a long time they did not find a way to do this. At first platinum had no practical application and cost twice as much as silver. People who had platinum had no idea what a valuable metal they were holding in their hands.

Isotopes of platinum

Platinum in nature is found in the form of four stable isotopes: 194Pt (32.9%), 195Pt (33.8%), 196Pt (25.2%), 197Pt (7.2%), which, when mixed with each other, form natural platinum or in the form of two radioactive isotopes of platinum: 190Pt (0.013%, half-life 6.9 1011 years), 192Pt (0.78%, 10 1015 years).

Platinum deposits

The main deposits of platinum, up to 90 percent, are located in five countries: South Africa, the USA, Russia, Zimbabwe and China.

Chemical properties of platinum

Platinum is the strongest inert metal with weak reactivity. Acids and alkalis do not react with platinum. Platinum can be dissolved in aqua regia. Bromine can be dissolved in platinum. Under normal conditions, platinum does not react chemically with other chemicals. In order for platinum to become reactive, it must be heated. Only after heating does platinum begin to react with peroxides and alkalis in the presence of oxygen. A thin platinum wire begins to burn in fluorine, releasing a large amount of heat. Platinum reacts less strongly with other non-metals (chlorine, sulfur, phosphorus). When heated strongly, platinum interacts with silicon and carbon and forms solid solutions.

In chemical compounds, platinum exhibits oxidation states from 0 to +6, of which compounds where platinum exhibits valency: +2 and +4 are stable. Platinum has many hundreds of complex compounds, all of them named after the famous scientists who studied them.

Finely dispersed platinum is an active catalyst for chemical reactions, while the metal itself does not undergo chemical changes. Platinum as a catalyst is used not only in chemical laboratories, but also on an industrial scale. For example, thanks to platinum, the reaction of hydrogen addition to aromatic compounds is accelerated (catalyzed), the reaction proceeds at room temperature and atmospheric pressure of hydrogen. Platinum black speeds up chemical reactions while remaining unchanged. For example, platinum black already under normal conditions oxidizes vapors of wine alcohol to acetic acid. Spongy platinum ignites hydrogen at room temperature. When spongy platinum (platinum black) comes into contact with a mixture of hydrogen and oxygen (explosive gas), a reaction occurs first, accompanied by quiet combustion, and then, due to the release of a large amount of heat, the platinum sponge becomes hot, which leads to an explosion of the detonating gas. Based on this chemical reaction a “hydrogen flint” was designed - a device for producing fire, which was previously used instead of matches.

Platinum is the strongest inert metal. In terms of its chemical properties, platinum is similar to palladium, only it has more stable chemical properties.

Platinum can only react with hot aqua regia.

Platinum does not react with acids and alkalis.

Platinum dissolves in hot concentrated sulfuric acid and liquid bromine.

Organic acids, like mineral ones, have no effect on platinum.

Platinum reacts with alkalis and sodium peroxide, halogens, only when heated.

Platinum reacts with sulfur, selenium, tellurium, carbon and silicon only when heated.

Platinum with oxygen forms volatile oxides when heated.

Platinum can form hydroxides (Pt(OH)2 and Pt(OH)4) upon alkaline hydrolysis of the corresponding chloroplatinoids. Platinum hydroxides exhibit amphoteric properties, that is, depending on conditions, they can have both acidic and basic properties.

Platinum with fluorine produces a chemical compound - platinum hexafluoride (PtF6), which is the strongest oxidizing agent, since platinum in this compound has the highest oxidation state of +6. Platinum hexafluoride is formed by burning platinum in fluorine under high pressure. This is the strongest oxidizing agent of all known chemical oxidizing agents; at room temperature it is capable of oxidizing even oxygen, forming the compound O2PtF6 and xenon to XePtF6.

The fluorination reaction of platinum to platinum fluoride - PtF4, occurs at normal pressure and temperature 350 - 400 degrees. Chemical compounds of fluorinated platinum are hygroscopic (they absorb moisture well) and decompose with water. Platinum tetrachloride PtF4, with water forms platinum tetrachloride hydrates. Platinum tetrachloride can be dissolved in hydrochloric acid to obtain chloroplatinic acids: H and H2.

Platinum forms complex compounds of the composition: 2- and 2-.

Platinum mining and production

After the discovery of South America (today this is the territory of Colombia), platinum was discovered in its lands, from the beginning this metal was mistakenly confused with silver, since these metals were very similar in color. Mined platinum in those days cost twice as much as mined silver. The low cost of platinum was due to ignorance chemical properties this element. People did not know how to use this metal practically. They didn’t even know how to melt it, since they didn’t know its melting point.

Later, jewelers discovered the property of platinum to perfectly alloy with gold. An alloy of gold and platinum allowed fraudsters to make fake gold. The density of platinum is greater than that of gold, so even minor additions of platinum to gold caused the gold metal to become significantly heavier. Gold items made from an alloy of platinum and gold looked very attractive and did not raise suspicions that these items were counterfeit. Such products became so popular in Spain that the Spanish king was forced to ban the import of platinum into the country, and ordered the remaining platinum reserves to be drowned in the sea. Even after the abolition of the law on the import of platinum into the country, this metal did not have much use and still remained a metal little known to science.

Little-known platinum was used to make chemical equipment and various devices that were used as catalysts. Platinum was mined in large quantities and exported from South America to Europe, where it was used irrationally. There was no industrial production of platinum at that time. Even when platinum began to be industrially mined in Russia, the mined noble metal did not have any worthy practical applications.

Platinum mined in Russia was mercilessly bought up and exported by other European countries and America. In Russia, even platinum coins were issued in denominations: 3, 6, 12 rubles. In terms of their value, platinum coins were slightly more expensive than silver coins by 5.2 times. Then the issue of such coins was stopped, and the coins themselves were withdrawn from circulation. It is believed that this happened because platinum prices began to rise in Europe, and platinum coins themselves began to cost more than their face value. After the cessation of minting platinum coins, platinum production in Russia fell.

Today, the world's reserves of exploration platinum amount to about 80,000 tons and are distributed among the countries: South Africa (87.5 percent), Russia (8.3 percent) and the United States (2.5 percent).

Application of platinum

In the 19th century, platinum began to be added as an alloying additive to produce high-grade steel.

Alloys of platinum with rhodium or platinum black were used as accelerators of chemical reactions.

Today, platinum is widely used in jewelry, medicine and dentistry.

Platinum is a refractory and chemically resistant metal, so various laboratory utensils, such as spoons and crucibles, are made from it.

Platinum alloyed with cobalt is used to make permanent magnets with remanent magnetization.

Special mirrors for laser technology are made from platinum.

Platinum alloyed with iridium is used to make stable and durable electrical contacts, which are used in the design of electromagnetic relays.

Since platinum is a highly inert, chemically low-active, very strong, durable and corrosion-resistant metal, various parts are coated with it using the electroplating method.

Platinum metal is used to make equipment that is resistant to aggressive environments, such as distillation retorts necessary for the production of hydrofluoric acid.

Platinum is used to make electrodes for the production of perchlorates, perborates, percarbonates, and peroxodusulfuric acid. Platinum produces all the hydrogen peroxide that is mined around the world.

Platinum is a material for anodes in electroplating, which do not dissolve in the electrolyte.

Anode rods made of platinum protect submarine hulls from corrosion.

Platinum is used to make heating elements in furnaces and resistance thermometers.

I cover microwave equipment elements (attenuators, waveguides, resonator elements) with platinum.

Platinum as part of chemical compounds is used in the manufacture of medical cytostatic drugs intended for the treatment of cancer patients. Such medicines cause necrosis of cancer cells, and then their death. These drugs include the first drug - cisplatin and the most modern and effective drugs: carboplatin and oxaliplatin.

Platinum, like silver and gold, is also used in jewelry. Up to 50 tons of platinum are used annually by the global jewelry industry. The main consumers of platinum until 2001 were the Japanese. Since 2001, only 50 percent of global platinum sales have come from China, down from 1 percent of the world's platinum products in 1980. Today, China remains a country where up to 10 million platinum jewelry with a total weight of up to 25 tons is sold annually. In Russia, demand for platinum accounts for 0.1 percent of all global sales.

Platinum, just like gold and silver, has its own alloys that are approved by the state for use. For Russia, the following platinum samples are provided: 850, 900, 950. Rarely and in small quantities, platinum alloys are used for the manufacture of jewelry. Platinum alloys are inferior to white gold. White gold is a composite alloy of gold with other metals, including platinum, palladium and nickel, the components of which give it a white color. 950 platinum alloy is often used to make jewelry. In addition to platinum, this alloy contains copper and iridium, which significantly increase its hardness.

The properties of platinum and palladium (a chemical element of the platinum group) are very similar. But palladium is currently not yet an independent, generally recognized metal for the production of jewelry. Today, palladium has the immediate prospect of becoming a precious metal for jewelry, since it is much cheaper in price than platinum, it is better processed, it has the same air oxidability as platinum, and it has a more intense white color.

Platinum is a heavy metal. In its chemical and physical properties, platinum is very similar to gold, mercury, thallium, lead and bismuth. Platinum can have a toxic effect on the human body, that is, cause poisoning. Platinum is not only a beautiful metal, but also poison. The lethal dose of platinum leading to death is 1 - 2 grams. Platinum oxide has a cauterizing effect on the skin. There are cases where, upon contact with platinum, changes were observed in the skin of the nails and hands. Platinum trioxide causes dermatitis.

Platinum nuggets are actually much more difficult to find than alluvial gold. Almost all of the platinum that has already been found is in microscopic pieces that are difficult to extract from the ore. They are not large enough to be picked up by a metal detector.

However, there are areas where platinum forms in large pieces, and when it gets into the stormy waters of rivers, it forms nuggets. Here's where they are located.

Ural

The Ural Mountains are the largest deposit of alluvial platinum nuggets in the world. Platinum is recovered from the gravel of streams and rivers throughout the region. This exceptionally rich mountain range is also famous for other rare earth metals.

Platinum nuggets that are found in the Urals are usually very small, but some of the large nuggets that have been found weigh more than a kilogram. Their cost is very high.

Conder Massif (Khabarovsk Territory)

The Far East is home to the largest platinum mine in Russia. Several tons of platinum are mined here every year. And gold. This is the only place on earth where you can find gold-plated platinum nuggets. And gold plated with platinum. The samples found here have a crystalline structure. Collectors purchase such “crystals” for incredible amounts of money.

Canada, British Columbia

Here, miners looked for gold, and the useless white metal, which was definitely not silver, was thrown away. Later, when the value of platinum became clear, a local “platinum fever” broke out. Locals tell a story from mouth to mouth about a Swede named Johansson, who in the Tulameen area collected 11 kg of platinum nuggets in a bucket, showed it to everyone, went to celebrate the event, for which he hid a bucket of precious metal somewhere. It got lost...

California

In the southern United States there is the only area with a platinum deposit. More precisely, the place where platinum is found in nuggets. This is the area around the small towns of Trinity, Siskiyou, and Junction City in California. There are nuggets weighing up to 100 grams here.

Other places

Platinum was almost always found in areas where gold was mined. Of course, not in all of them. Sometimes prospectors are lucky in Chukotka, Alaska, Colombia (this time in South America).