328. ------. [CARPENTER, G. B.] (E. I. du Pont de Nemours & Co.). Formic Acid. United States Patent 2,023,003, Dec. 3, 1935. Chem. Abs., vol. 30, 1936, p. 736.

Patent Abstracts

Gaseous mixture of CO and steam (Suitably at a temperature of about 325º) is passed over a catalyst containing primary Ca phosphate or other suitable acid salt of the acidic oxides of P, As, W, Mo, U, Cr, V, B, Si, or Zr. Pressures of 25-900 atm. may be used.

See also United States Patent 2,001,659 (abs. 3965).