Wollaston, William Hyde, platinum

William Hyde Wollaston (1766-1828) found rhodium in crude platinum. 

Rhodium - the atomic number is 45 and the chemical symbol is Rh. The name derives from the Greek rhodon for rose because of the rose color of dilute solutions of its salts . It was discovered by the English chemist and physicist William Hyde Wollaston in 1803 in a crude platinum ore. 

In 1803 William Hyde Wollaston, a British physician who became famous for his research in metallurgy, mineralogy, and optics, succeeded in extracting a white metal from platinum. He named the new element palladium, after the asteroid Pallas, which had just been discovered the previous year. In the same year the English chemist Smithson Tennant obtained two new metals, which he named iridium and osmium, from platinum. And in 1828 the Russian chemist Karl Karlovich Klaus reported that he had obtained three new metals from platinum mined in the Urals. However, the existence of only one of them, which Klaus called ruthenium, was confirmed. 

British scientist William Hyde Wollaston Anticorrosive, soft metal often found combined with platinum useful in dentistry, as a cancer-fighting agent easily absorbs hydrogen and used as a purifier of that gas. 

At the start of the nineteenth century, platinum was refined in a scientific manner by William Hyde Wollaston, resulting in the successful production of malleable platinum on a commercial scale. During the course of the analytical work, Wollaston discovered palladium, rhodium, iridium, and osmium. Ruthenium was not discovered until 1844, when work was conducted on the composition of platinum ores from the Ural Mountains. 

Although platinum was introduced to Europe in the mid-18th century, it was first made commercially available in large quantities and in malleable form in 1805 by the English chemist William Hyde Wollaston. Previous attempts at consistently producing malleable metal were hindered by chemical purification techniques that gave platinum contaminated with deleterious metallic impurities. Richard KnighPs improved process of 1800 was carried out on a suitable sample of crude ore, and analysis of the purified platinum by spark source mass spectrometry (SSMS) indicates an impurity level of about 6%. Reconstruction of Wollaston s purification procedures, coupled with SSMS analysis, indicates that his product was over 98% pure. His superior chemical purification techniques, coupled with improvements in the powder consolidation method, explain Wollastons success. 

Malleable bar platinum became generally available to the European scientific community for the first time in the early months of 1805. The new noble metal, known in Europe only since the mid-18th century, had resisted all prior efforts by experimenters to transform consistently the crude alluvial ore into a chemically pure, malleable metal. Bar platinum was a product of the chemical and metallurgical researches of the English natural philosopher William Hyde Wollaston, who had spent much of the previous 5 years developing and improving a satisfactory production process. The details of his chemical and tech-... 

Palladium was discovered along with rhodium in 1803 by English chemist William Hyde Wollaston (1766—1828). Wollaston had been studying platinum ores, probably taken from South America. 

Rhodium is named after the Greek rhodon, meaning rose color. William Hyde Wollaston (1766-1828) discovered rhodium in 1804 when he removed platinum and palladium from ore he had received from South America and found a red residue. Rhodium is rare, but it is used commercially in electrical parts and jewelry and as a catalyst. 

William Hyde Wollaston first described this type of adhesion experiment in 1829. He was interested in making dense and strong wires from platinum and other rare metals, such as palladium and osmium, which he had just diseovered. Platinum is so hard and refractory that it is extremely difficult to work by ordinary melting and casting techniques. Wollaston prepared the platinum in fine particle form by precipitating the metal from an acid solution which had been used to remove impurities. This produced a muddy mixture of water and particles which were cleaned by washing, then dispersed by milling in a wooden mortar and pestle. Wood was used to limit contamination since it would burn out later. 

History. William Hyde Wollaston discovered rhodium in 1804 in crude platinum ore from South America soon after his discovery of another element, palladium. He dissolved the ore in aqua regia, neutralized the acid with sodium hydroxide (NaOH), and precipitated the platinum by treatment with salmiac (i.e., ammonium chloride, NH Cl) as ammonium hexa-chloroplatinate (NH PtClJ. Palladium was then removed as palladium cyanide by treatment with mercuric cyanide. The remaining material was a red material containing rhodium chloride salts from which rhodium metal was obtained by reduction with hydrogen gas. 

William Hyde Wollaston (Figure 32.1) was more significant than anybody else in platinum research, and even for the technology of the platinum metals. He and his colleague Smithson Tennant showed that naturally occurring platinum is an alloy, con-... 

Harrison was also the first to install a new technology to produce concentrated acid. The standard Contact acid was too weak for some applications which required stronger acid but not necessarily fuming. At high concentration, even lead reacted with sulfuric acid. A new distilling technology used platinum stills, a process developed by Erick Bollman, a friend of Lafayette, in 1813. Platinum was not the exotic, expensive element of today. Bollman had found one of the few uses for this material. Platinum was relatively difficult to manipulate and a method had only recently been developed by William Hyde Wollaston (1766 - 1828), whom Bollman knew. Harrison used the original still until 1828. 

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