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The Early History of Catalysis

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The Early History of Catalysis The Early History of Catalysis By Professor A. J. B. Robertson Department of Chemistry, King’s College, London One hundred and forty years ago it was Berzelius proceeded to propose the exist- possible for one man to prepare an annual ence of a new force which he called the report on the progress of the whole of “catalytic force” and he called “catalysis” the chemistry, and for many years this task was decomposition of bodies by this force. This undertaken by the noted Swedish chemist is probably the first recognition of catalysis J. J. Berzelius for the Stockholm Academy of as a wide-ranging natural phenomenon. Sciences. In his report submitted in 1835 and Metallic catalysts had in fact been used in published in 1836 Berzelius reviewed a num- the laboratory before 1800 by Joseph Priestley, ber of earlier findings on chemical change in the discoverer of oxygen, and by the Dutch both homogeneous and heterogeneous sys- chemist Martinus van Marum, both of whom tems, and showed that these findings could be made observations on the dehydrogenation of rationally co-ordinated by the introduction alcohol on metal catalysts. However, it seems of the concept of catalysis. In a short paper likely that these investigators regarded the summarising his ideas on catalysis as a new metal merely as a source of heat. In 1813, force, he wrote (I): Louis Jacques Thenard discovered that ammonia is decomposed into nitrogen and “It is, then, proved that several simple or compound bodies, soluble and insoluble, have hydrogen when passed over various red-hot the property of exercising on other bodies an metals, and ten years later, with Pierre action very different from chemical affinity. Dulong, he found that the activity of iron, By means of this action they produce, in these bodies, decompositions of their elements and different recombinations of these same elements to which they remain indifferent.” Louis Jacques Th6nard 1777-1857 Born at Nogent-sur-Seine, The‘nnrd cane to Yoris at the age of 17 during the Reign of Terror to study pharmacy. His keenness brought him to the notice of Vauquelin and Fourcroy, both of whom ad- vanced his career. In 1804 he replaced Vuuquelin in the chair of chemistry at the CoEl?ge de France while in 1810 he was appointed Professor at the &ole Polytechnique and succeeded Fourcroy in the Academie des Sciences. In 182.5 Charles X crented him Baron. From the portrait in the Wellcome Institute of the History of Medicine Platinum Metals Rev., 1975, 19, (2), 64-69 64 Humphry Davy 1778-1829 Davy tau(5ht himself by reading Lavoisier’s “Traite Elementaire de Chimie” and began his career at the newly formed Pneumatic Institute at Rristol. In 1801 he toas ofercd a post at the Royd Institution by Count Rumford, and it was here that he carried out most of his brilliant experimental work andgave his famous lectures. In 1812 he was knighted by the Prince Regent and he wus elected President of the Royal Society in 1820. From the portrait by Sir Thomas Lawrence in the posses- sion of the Royal Society copper, silver, gold, and platinum for de- Later he became Professor at the Conserva- composing ammonia decreased in the order toire des Arts et Metiers, and after winning a given. This is one of the earliest recorded lottery, married the daughter of Dtsormes. examples of a pattern of catalytic activity. That a chemical substance can speed up a Thenard, the son of a peasant, after experi- chemical reaction without itself being chemic- ence with Vauquelin in Paris as a laboratory ally changed became clear in a research on the boy, became assistant and later Professor at decomposition of hydrogen peroxide, carried the lkole Polytechnique. In 1857, then a peer, out by L. J. Thenard, who announced his he became Chancellor of the University of discovery of this substance in 1818. Thenard Paris. His collaborator Dulong was Professor had become interested in barium peroxide, of Physics in the &ole Polytechnique, later probably because of the notable discovery by becoming Director. He is, of course, famed Davy in 1807 of sodium and potassium, which for the law of Dulong and Petit. He also he prepared by the electrolysis of their moist proposed a hydrogen theory of acids in- hydroxides. Davy’s first Bakerian lecture in dependently of Davy. 1806 “On some Chemical Agencies of Elec- Homogeneous catalytic processes have been tricity” described work of such importance used by mankind for some thousands of that the 3000 francs prize given by Napoleon I years, for example in fermentation. Perhaps was awarded to him. Napoleon seems to have the first attempt at a rational theory of catalysis been somewhat peeved that the prize went to is the intermediate compound theory proposed an Englishman when a state of war existed by Charles Bernard Desormes and Nicolas between England and France, and, noting the Clement (2) for the homogeneous catalytic vital part the large Royal Institution voltaic effect of nitrogen oxides in the lead chamber pile had played in the research, he ordered process for the manufacture of sulphuric acid. two large voltaic piles to be built. Perhaps he This particular process was later discussed adopted the type of argument we note even more fully by Humphry Davy, and has now from some political circles, that two received a huge amount of attention and voltaic piles will do twice as much useful work discussion since these early times. as one, irrespective of who originates the Clement studied science in Pans and ideas to be tried out with the piles. Thtnard became assistant at the Ecole Polytechnique. probably investigated the alkaline earth Platinum Metals Rev., 1975, 19, (2), 65 The opening page of the manu- srript of Sir Humphry Dauy’s paper read to the Royal Society on Junuary 23rd. 1817, “Some new experiments and ohservations on the combination of gaseous mixtures, with an account of a method for keeping a continued light in mixtures of inflammable gases and air tuithoutflame”. The paper goes on: “I had intended to expose jine platinum wires to oqgen and olrJant gas and to oxygen and hydrogen during their slow cornbination under different circumstances, when I zuas acci- dentally led to the knowledge oj’ the fact, and at the same time to ihe dixooery of a ncw and curious series of phenonoena.” Duvy had discovered heterogeneolts catalytic oxidation oxides with the initial aim of electrolysing safety-lamp. When additional coal gas was them. The work he did on the reaction of introduced into the lamp, the flame went out barium peroxide with nitric or hydrochloric but the platinum wire remained hot for many acid led to the discovery of hydrogen peroxide. minutes. Davy immediately deduced that the This he found to decompose when in contact oxygen and coal gas combined without flame with many solids, some of which were not when in contact with the hot wire, thereby chemically changed. He also found that the producing enough heat to keep the wire action of metals in bringing about decomposi- incandescent. A hot platinum wire introduced tion became more vigorous as the metal was into a mixture of coal gas and air immediately reduced to a finer state of subdivision. became incandescent. Furthermore many combustible vapours mixed with air were Humphry Davy’s Classic Paper found by Davy to produce the same effect. The first clear realisation that chemical Davy had discovered the phenomenon of reaction between two gaseous reactants can heterogeneous catalytic oxidation. occur on a metal surface without the metal Only platinum and palladium wires were being chemically changed is found in a paper effective; wires of copper, silver, gold and by Humphry Davy (3) published by the iron were ineffective. This is one of the Royal Society in 1817. This describes “the earliest recorded patterns of catalytic activity. discovery of a new and curious series of In these researches Davy was assisted by phenomena”. During the researches which Faraday but it is unclear whether Faraday led to the miners’ safety-lamp, Davy fixed a contributed to the development of the ideas fine platinum wire above a coal-gas flame in a or acted mainly by carrying out Davy’s Platinum Metals Rev., 1975, 19, (2), 66 instructions. The two-man team which made and Thenard (6) in Paris, who discovered that these discoveries about heterogeneous catalysis palladium and iridium could also act at must have been one of the strongest in the ordinary temperatures whereas cobalt, nickel, whole history of chemistry. rhodium, silver and gold acted catalytically In order to initiate catalytic oxidation the only at higher temperatures. Their note wires used by Davy needed to be hot, but in actually appeared in the Annales de Chimie et 1820 Edmund Davy (4), Profcssor of de Physique before Dobereiner’s paper because Chemistry at Cork in Ireland, formerly his discovery was communicated privately by Assistant: at the Royal Institution, and cousin Liebig to Dulong and Thenard. of Humphry Davy, prepared a finely-divided Dobereiner’s work had, however, been platinum catalyst of such high activity that it communicated from Paris to Faraday in a acted at room temperature. When this letter of September 16th, 1823, from J. N. P. catalyst was dropped on to any porous Hachette and within a few days Faraday substance moistened with alcohol, oxidation had proceeded to repeat the experiment and occurred so rapidly that the catalyst became confirm the findings. In a brief note (7) red hot. signed merely “M. F.” he wrote “it was communicated to me by M. Hachette and Dobereiner’s Experiment having verified it I think every chemist will J.
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