Bosch, Carl

(b. Cologne, Germany, 27 August 1874; d. Heidelberg, Germany, 26 April 1940)

chemistry.

The Bosch family was of Swabian peasant stock. Two sons had already left the farm by the second half of the nineteenth century, however. The younger of the two founded an electrotechnical firm that later became world-famous. The older of the two, Carl, opened a gas and plumbing equipment business.

The latter gave his name to his son, the eldest of his children. From his very young days, the boy showed a special talent for the natural sciences and technology, which his father ardently encouraged. The younger Bosch was not allowed to study chemistry until he had first completed a few semesters of training in an ironworks and then a few semesters of training in an ironworks and then a few semesters of mechanical engineering. He then turned to chemistry in Leipzig, where, after four years, he obtained his doctorate. He applied for a position at the Badische Anilin- und Sodafabrik in Ludwigshafen and was accepted. Quite by chance, he touched upon the field that would subsequently become his lifework. Wilhelm Ostwald, a winner of the Nobel Prize, claimed to have found a process for obtaining ammonia from nitrogen and hydrogen by conduction over fine wire. Bosch was entrusted with supplementary testing and quickly found the error that Ostwald had made and the reasons for it. Thereupon he was given the task of studying the nitrogen question further. Only the use of atmospheric nitrogen was feasible. Use of the electric arc was not possible because of the high current requirements in Germany. Numerous experiments were carried out. New problems continually arose, but there were so many positive results that a breakthrough appeared near.

In 1909 Fritz Haber of Karlsruhe began work on the synthesis of ammonia, employing unusually high pressures and temperatures. Bosch undertook to transform Haber’s laboratory experiments into large scale technological ones, which in turn developed into a huge industry within five years. Haber’s technically unsuitable catalysts had to be replaced. After thousands of experiments, iron with admixed alkaline material proved to be especially suitable. Equipment had to be built that would be capable of withstanding high pressures and temperatures. The furnaces, which were first heated from outside, lasted only a few days; the iron lost its carbon content, and thereby its steel properties, because of the hydrogen, brittle iron carbide being the result. Bosch devised a twin tube that allowed the hydrogen to escape through tiny openings. After numerous experiments, he found a solution to the heat problem whereby he introduced the uncombined gases into the furnace and, accordingly, produced an oxyhydrogen flame, the temperature of which could be regulated according to the quantity of oxygen added. The combination of nitrogen and metals was attempted. “The work was conducted at enormous cost.” The gases required for synthesis had to be obtained in an exceptionally pure state. The separation of the ammonia that had formed from the untransformed gases was extremely difficult. Bosch’s technological know-how proved itself to be the most outstanding aspect of his work, and he was always personally active in all practical testing of his equipment.

Bosch also undertook another experiment in high pressure engineering, an attempt to obtain urea from ammonium carbamate, and developed the methanol synthesis used in the manufacture of formaldehyde. Finally he tackled the problem of carbon hydrogenation and the production of synthetic rubber.

In 1925 Bosch became president of I. G. Farben, and in 1931 he shared the Nobel Prize with Bergius “for the discovery and development of chemical high-pressure methods”.

He died after a long illness.

BIBLIOGRAPHY

I. Original Works. Bosch’s writings include “Verfahren zur Darstellung von Bariumoxyd und von Cyaniden”, in Chemisches Zentralblatt (1907), 1999; “Verfahren zur Darstellung von Mono-und Dichlorhydrin aus Glycerin und gasförmiger Salzsäure,” ibid. (1908), 1655; “Verfahren zur Darstellung von Aluminiumstickstoffcverbindungen”, ibid., (1912), 865; “Verfahren zur Herstellung von Ammoniak aus seinen Elementen mit Hilfe von Katalysatoren”, ibid. (1913), 195; “Stickstoff in Wirtschaft und Technik”, in Naturwissenschaften, 8 (1920), 867–868; “Entwicklung der chemischen Hochdrucktechnik bei dem Aufbau der neuen Ammoniakindustie,”, in Les prix Nobel en 1931 (Stockholm, 1933); and “Probleme grosstechnischer Hydrierungs-Verfahren”, in Chemische Fabrik, 7 (1934), 1–10.

II. Secondary Literature. For a discussion of Bosch’s life and work, see K. Holdermann, “Carl Bosch, 1874–1940”, in Chemische Berichte, 90 (1957), xix-xxxix; and Carl Krauch, “Carl Bosch zum 60 Gedächtnis,”, in Angewandte Chemie, 53 (1940), 285–288; see also the unsigned tribute “Carl Bosch zum 60 Geburstag”, ibid., 47 (1934), 593–594.

GÜnther Kerstein