Paul Sabatier Biography

World of Scientific Discovery on Paul Sabatier

Paul Sabatier, who shared the 1912 Nobel Prize in chemistry with his countryman Victor Grignard, spent thirty-two years of a fifty-year career studying heterogeneous catalysis, especially the catalytic hydrogenation of organic compounds over finely divided metals.

Born on November 5, 1854, in Carcassone, France, Sabatier attended school in Carcassone, where his uncle was a teacher. When his uncle transferred to the Toulouse Lycée, Sabatier followed. While atToulouse, he used his free time to attend a public course in physics and chemistry that gave him a taste for science.

Accepted at both the École Polytechnique and the École Normale Supérieure in 1874, he entered the latter and graduated atthe head of his class in 1877. He worked as an instructor in Nîmes for a year, but teaching secondary school physics was not what he wanted,and he returned to Paris as an assistant to Marcellin Berthelot at the Collège de France. There, in 1880, he earned his doctoral degree with a thesis on metallic sulfides.

After a year of teaching physics at the Faculté des Sciences at Bordeaux, he returned to Toulouse in 1882 to teach physics at the Faculté des Sciences there. In 1883, his duties expanded to include chemistry, and in 1884, at the age of thirty, the earliest allowable, hew as appointed professor of chemistry. He remained in that post for therest of his career, refusing offers from the Sorbonne to succeed Henri Moissan and from the Collège de France to succeed Berthelot. He was chosen Dean of the Faculty of Science in 1905, an office which he held for over twenty-five years. In addition to his research and teaching during this period, he was instrumental in the creation of schools of chemistry, agriculture,and electrical engineering at Toulouse. Even after his official retirement in 1929, he continued, by special permission, to lecture untilf ailing health forced him to stop in 1939. Sabatier died on August 14, 1941.

For his doctoral research and during his first fifteen years at Toulouse, Sabatier worked in the area of inorganic chemistry. His early work on the sulfides, hydrogen sulfides, and polysulfides of alkali and alkaline earth metals helped to clarify a complicated area of chemistry.He prepared the first pure sample of dihydrogen disulfide and was the first to make silicon monosulfide and tetraboron monosulfide as well as boron and silicon selenides. He carried out a number of thermochemical studies of the hydration (addition of H₂O) of metal chlorides and chromates and various copper compounds and was a pioneer in the use of absorption spectroscopy to study chemical reactions. Absorption spectroscopy exploits the unique patternsof light absorption characteristic of chemical substances to identify them. Spectroscopes scatter the light with a prism so that the dark absorption lines become visible in the spectrum.

In the 1890s it occurred to Sabatier to see if nitric oxide would produce a compound with nickel analogous to the recently discovered compound of nickel and carbon monoxide. These experiments, conducted withthe chemist Jean-Baptiste Senderens,were not very fruitful, though some nitrogen compounds of copper, cobalt,nickel, and iron were obtained by the reaction of nitrogen dioxide withthe metal. Sabatier then thought to use acetylene, an organic compound,but learned that Moissan and François Moreau had passed acetylene over powdered nickel made by heating nickel oxide with hydrogen and reported the formation of only carbon, some liquid hydrocarbons, and a gas they thought to be hydrogen.

In 1897, after being assured that Moissan and Moreau had no plans to continue their acetylene studies further, Sabatier and Senderens tried the reaction using the gas ethylene, another hydrocarbon. The experiment was successful and thus solidified Sabatier's switch to organic (carbon-based) chemistry. The result was again the formation of carbon, liquid hydrocarbons, and a gas, but on analyzing the gas, they found it to be mostly ethane and only a little hydrogen. Appreciating that the ethane could only have arisen through the addition of hydrogen to the ethylene (hydrogenation), they tried passing a mixture of ethylene and hydrogen over finely divided nickel and found that the smooth hydrogenation of ethylene took place at only a little above room temperature (30-40°C). For the next thirty-two years, Sabatier and his students investigated the heterogeneous catalysis (a process in which a third substance, or catalyst, influences therate of a chemical reaction) of a variety of organic reactions by metals and metal oxides.

On the basis of his studies, Sabatier explained the catalyticaction by the formation of unstable intermediate compounds between thecatalyst and the reactant(s). This view, opposed to an earlier theorythat the effect was due only to local extremes of pressure andtemperature in small pores of the catalyst, proved to be correct andrevolutionized organic chemistry.

In 1912, Sabatier's work was recognized by the shared award of the Nobel Prize in chemistry. The following year, he summed up his fifteen years of work on catalysis and reviewed the accumulating literature inthe field in the book La Catalyse en chimie organique. Although his pioneer work was basic to the development of importantindustrial processes such as the catalytic cracking of petroleum to increase the yield of gasoline and the hydrogenation of vegetable oils to make shortening, Sabatier did not interest himself in such practical applications, nor did he profit from them.