The conversion of coal to petroleum: its German roots

Abstract

This paper [1] examines the work of Friedrich Bergius, the inventor of high-pressure coal hydrogenation in the period 1910–1925.

The paper traces Bergius's development of high-pressure coal hydrogenation from a laboratory-scale process to a small factory-size operation at Rheinau-Mannheim, Germany. Bergius carried out several thousand experiments, requiring the testing of more than 200 different kinds of coal, before bringing his hydrogenation process to a successful conclusion. In his factory, where he spent several million dollars in research and employed 150 men, Bergius demonstrated for the first time the possibility of establishing a German synthetic petroleum industry.

This history of coal hydrogenation shows the difficulties Bergius faced in expanding his process from the laboratory-scale to a small industry. The major problems he confronted and successfully solved were: (1) providing enough hydrogen gas to convert coal into synthetic petroleum, (2) working at the high pressures required for the conversion, and (3) regulating the reaction's temperature. Because the reaction was exothermic and sensitive to temperature change, accurate temperature control was a major accomplishment.

In spite of Bergius's successes, two other problems remained unsolved. Bergius did not investigate the influence of different catalysts on the hydrogenation reaction, and his process was a one-stage operation; the hydrogenation of coal and the splitting of the products formed took place in one step. This procedure resulted in a smaller amount of the reaction products splitting into gasoline-size molecules. The gasoline was, in addition, of low quality, and without refining it could not compete with gasoline obtained from natural petroleum.

The major emphasis in the study of the early German coal hydrogenation programs has been on the scientific and technological developments that Bergius encountered, but not to the exclusion of the social, political, and economic factors that accompanied its rise. It illustrates, for example, the difficulties that Bergius, scientist and entrepreneur, faced in continually trying to raise money to keep his project alive and his efforts to market his product by entering into different patent arrangements in Germany and internationally.