2001. ------. [LARSON, A. T.] (E. I. du Pont de Nemours & Co.). Carboxylic Acids. United States Patent 2,448,375, Aug. 31, 1948. Chem. Abs., vol. 43, 1949, p. 670.

Aliphatic carboxylic acids, such as EtCO₂H, are prepared by the reaction of steam, CO, and an olefinic hydrocarbon at 500-1,500 atm. in the presence of a catalyst, such as NiCO or CoCO and active C, at 200°-400°.