DISCOVERY and EARLY HISTORY of PLATINUM ... - ACS Publications

L ONG before it was found in the Ural mountains, platinum constituted an object of research for a very versatile Russian statesman, Apollos Apollo-...
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DISCOVERY and EARLY HISTORY of PLATINUM in RUSSIA B. N. MENSCHUTKIN

L

ONG before it was found in the Ural mountains, platinum constituted an object of research for a very versatile Russian statesman, Apollos Apollosovif Musin-Pugkin (1760-1805). He was vice-president of the Mining College in St. Petersburg, honorary member of the Russian Academy of Sciences, and member of the Royal Society of London; he created in 1804 the Mining Cadet Corps of St. Petersburg-the Mining Institute of the present day. The last years of his life were spent as administrator in the Caucasus, where he still found time for work in his chemical laboratory a t Tiflis. The results of Musin-Pugkin's chemical investigations were published in the Annales de Ch.imie up to the year 1804. He seems to have been the first toprepare pure, colorless and transparent phosphorus; he discovered chrome alum (1800), sodium tungstate, etc. His work on platinum was begun in 1797. In the paper "Sur les sels et les $recipit6s de &tine" are contained determinations of the solubility of ammonium chloroplatinate, a description of the preparation of magnesium and barium chloroplatinates and of beautiful crystals of sodium chloroplatinate (regarded a t the time as uncrystallizable). He obtained platinum amalgam by triturating quicksilver with ammonium chloroplatinate, also by triturating platinum sponge powder with the fivefold quantity of mercury. He prepared malleable platinum out of this amalgam by placing it in a wooden mold, pressing out the excess of mercury and gradually heating the mold to the temperature of evaporation of the mercury; thereafter the molds were burned and the metal brought to a white heat for two hours or more: thus was produced ,malleable platinum which could be hammered like silver. Let it be recalled that at this time only one method for working platinum was known, namely, by fashioning objects out of an alloy of platinum and arsenic, and heating until the arsenic was driven off (the process of the jeweler Jannety, communicated by Lavoisier to the French Academy of Sciences in 1790). The last investigations of Musin-Puikin on platinum were published only in Russian in 1805: they deal (I) with the preparation and properties of fulminating platinum, (2) with the best method of separating platinum from iron (by means of sodium carbonate), and (3) with the discovery, preparation, and properties of platinum sulfide. All of the essays of Musin-Pugkin are written in a clear, terse style and testify to his great observational skill and capacity for work. Indications of the existence of platinum in Russia were obtained prior to the year 1819; a white metal was observed in the gold placers of the eastern (Si-

berian) flanks of the Ural mountains to the south of Ekaterinburg (since 1918 Sverdlovsk). In 1819 a specimen of it was brought for investigation to the Gold-smeltingLaboratory of Ekaterinburg, and samples of the white metal were received also during subsequent years. The scientific study of it was made only in 1822, when I. I. Varvinskij was appointed director of the Laboratory. He made several tests indicating that the metal contained platinum, and sent all that was left to St. Petersburg where it was investigated in the chemical laboratory of the Mining Cadet Corps by Bergfirobierer V. V. Liubarskij who showed it to be osmiridium identical with that found in America (Columbia). A further quantity of the white metal, about 100 grams, reached St. Petersburg in 1824, and V. V. Liubarskij made a quantitative analysis. The metal had the following composition: 60% iridium, 30y0 osmium, 5% iron, 2% platinum, and 0.7% gold. During the year 1824 platinum was discovered to the north of Ekaterinburg in the Ural. The newly appointed director of the Goroblagodat Mining District, N. R. MamySev, was certain that this region contained both gold and platinum. Accordingly, in the summer of that year he sent out several mining officers to make the necessary explorations. These were crowned with complete success: during August and September of 1824 three rich placers were found, two containing gold and platinum and one having almost pure platinum. The next summer witnessed an immense increase in the number of platinum placers discovered, and was the first season of platinum production. In 1825 eleven fiouds (180.14 kilograms) was extracted. This quantity for that time was prodigious, as America had produced up to 1825 (since 1741) but a little over one ton of platinum. Forthwith platinum was declared a state monopoly. The abundance of the metal naturally raised questions as to its use. Here again the energetic N. R. Mamykv came to the fore. He commissioned Oberbergmeister A. Archipov to investigate possible applications of platinum. During the year 1825 A. Archipov obtained malleable platinum by the method of Jannety, made a number of objects out of it, and showed that they were equal to those manufactured in Paris. He further investigated the alloys of platinum with iron and copper. Of the many alloys prepared we may mention those containing (a) 80% Pt, 20Yo Cu, and (b) 67% Pt, 33% Cu. Both were found to be almost completely acid-resistant, the latter taking on a beautiful polish and being of a lovely, light rose color. Of the iron alloys the most remarkable was obtained by adding 1.3% of platinum to carbon steel; this alloy was 26

found to be extremely hard and not brittle when quenched, resembling in its properties the famous East Indian wutz. Meanwhile the investigation of platinum was carried on in the Mining Cadet Corps a t St. Petersburg, under the direction of P. G. Sobolevskij. Petr. Grigorievit Sobolevskij is an outstanding figure in the early history of Russian platinum. Son of a surgeon, born in 1781, he began his career as a military officer, but left the military service in 1804 and thereafter occupied administrative and technical posts. In the beginning of 1826 he was appointed director of the large new chemical laboratory just erected a t the Mining Cadet Corps. He was one of the professors of chemistry of this

secret; he disclosed i t only two years later, in 1828, in the Bakerian lecture. P. G. Sobolevskij gave the first public demonstration of the new method in the chemical laboratory of the Mining Cadet Corps on January 23rd, 1827, in the presence of the director of the Mining Corps, E. V. Karneev, and a large number of visitors. One of the latter, N. P. SEeglov, the first professor of physics a t the University of St. Petersburg (which was opened on February S, 1819), has left us a description of this demonstration which is memorable in the history of Russian platinum. Two mouths later, on March 21st, P. G. Sobolevskij made the communication in a formal meeting of the Scientific Committee on Mining

Mining 1nstit;te

Institute, corresponding member of the Russian Academy of Sciences, and held many other commissions. His sudden death occurred on October 24, 1841. First of all, accurate analyses of platinum from the Goroblagodat district were made by V. V. Liubarskij, who was throughout associated with P. G. Sobolevskij in this work. These showed that the metal was crude platinum, containing little osmiridium. A method for obtaining pure platinum on the large scale was worked out, consisting of dissolving the crude platinum in aqua regia and precipitating ammonium chloroplatinate by ammonium chloride. But the attention of P. G. Sobolevskij and V. V. Liubarskij was chiefly occupied by the quest for a cheap method for the production of malleable platinum from the platinum sponge which resulted from the calanation of the ammonium chloroplatinate. They succeeded in discovering it in the latter half of 1826. This method is essentially the same as that used by W. H. Wollaston in London. In 1826 Wollaston's process was still a

and Salt Industries; the members were shown different objects, some medals, and an ingot weighing six pounds, of Russian platinum. For this invention both P. G. Sobolevskij and V. V. Liubarskij received special gifts from the Emperor Nicholas I. In the Mining Journnl of 1827 P. G. Sobolevskij thus describes the process: The method is as follows: Pure platinum sponge is packed as tightly as possible into an iron mold having the form of a hollow cylinder, and compressed strongly by means of a screw press. On takmg it out of the mold a compact metallic disc is ohtained. Platinum in this state is not malleable, the force of cohesion between the particles docs not withstand sharp b l o w c t h e disc breaks and crumbles. In order to transform such discs into malleable platinum it is only necessary to bring them (in the same mold) to a white heal and in this state l o compress them again. A t once the disc completely changes its appearance: the granular structure becomescompact and thedisc can be forged.. . Hereafter the discs are hammered into bands or bars in the usual way.

Afterward the method was simplified and is thus

described in the "Fundamentals of Pure Chemistry," 1831, of G. Hess,* where the description is supplemented by the figure which is reproduced herewith. On the steel bedplate of the press, C, is placed a hollow iron cylinder, a [the mold of the former description]; it is filled with powdered platinum sponge (usually three pounds). The platinum powder is covered by a steel cylinder, b, easily fitting the tube, and is compressed by means of the press. Platinum is obtained in the form of a compact metallic disc. . . . Several of these discs are then placed in one crucible and brought to white heat. The particles of platinum weld together, the discs contract . . . . . the higher the temperature the better for subsequent treatment.. . . . The discs are thereupon hammered a t the forge into hands just like iron.

Now that a method of working platinum had been invented, platinum could be freely used for different purposes. The production rose every year; in 1826, 13.5 p o d s were produced; in 1827, almost 26 p o d s ; in 1828,95 pouds; in 1829,78.5 p o d s ; and in 1830,106.5

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* Germain

Henri Hess (in Russian, German Ivanovi6 Gess)

was one of the foremost Russian physical chemists of the second

quarter of the nineteenth century. Born in Geneva in 1802, he early came t o Russia. A medical doctor by profession, he did not practice, hut was professor of chemistry and inspector of the Mining Cadet Corps after 1832, one of the founders of the Technological Institute of St. Petersburg (1828). member of the Russian Academy of Sciences (1834), and professor of chemistry in other higher institutions of St. Petersburg. He wrote an excellent textbook, "Fundamentals of Pure Chemistry," the first edition appearing in 1831 and the last, the seventh, in 1849. I n 1835, together with P. G. Sobolevsltij, S. J. Neraev, and M. S. Soloviev, he devised a scheme of rational Russian chemical nomenclature which is used to this day. He is widely known for his work on the heat of chemical reactions (1836-1841). The "law of Hess" is t o be found in every textbook of physical chemistry. He died in 1850 a t the early age of forty-eight years.

p o d s (one @WE = 16.38 kilograms; 61 p o d s = 1 ton). The government gave platinum freely to Russian and foreign scientists for investigation, and during the years 1825-1830 these donations amounted to nearly one p o d . In the year 1825 N. R. MamyBev proposed to use platinum for coinage; this proposal received the sanction of Nicholas I and was realized by the Minister of Finance, Count E. F. Kankrin. The first platinum coins were minted in 1828, and some of these were sent t o A. von Humboldt, who advised E. F. Kankrin on certain questions pertaining to the coinage. The coins were of three denominations; three roubles, containing 2 zolotniks 41 dolia (= 10.352 grams) of pure platinum; six roubles, containing 4 zolotniks 82 dolia (= 20.704 grams) of platinum; and twelve roubles, containing 9 zolotniks 68 dolia (= 41.408 grams) of pure platinum. They were minted during all of the following years up to 1845 inclusive, when the successor of Count E. F. Krankrin, Minister of Finance E. VronEenko, discontinued the issue, being afraid of counterfeits. During the eighteen years 1828-1845 almost 1,400,000 pieces were made, to the nominal sum of 4,251,843 roubles, containing 899 p o d s 30 pounds (= 14.75 tons) of platinum. Some of the issues are exceedingly rare, as for instance those of 1839 and 1840, when only one or two coins of each denomination were struck. Up to 1845 inclusive some 2000 p o d s (= 32.8 tons) of a u d e platinum were extracted, so that the amount used for coinage is responsible for more than half of the total quantity of pure platinum mined. In 1846 platinum coins were withdrawn from circulation, and the public returned to the Treas-

ury 3,263,292 roubles worth of platinum money at about three-quarten of the amount which had been issued. At that time platinum did not command a high price. Suspension of platinum coinage marks the end of the first period in the history of Russian platinum. We shall not follow it farther, only the reader that the sixth of the platinum metals, ruthenium,

was discovered by Professor K. K. Klaus of the Kazan University in 1844, as related in "The Discovery of the Elements," by Mary Elvira Weeks U. CHEM.EDUC.. 9, 1028 (1932)l. NOTE: The letters used in transcribing Russian names are like ch in chain; like sh in shall; ch like in hall; y as in Polish, a very deep i (there is no English equivalent) and j as y in jay or joy.