2680. PIER, M., SIMON, W., AND JACOB, P. (I. G. Farbenindustrie A. G.). [Catalysts.] German Patent 693,985, June 27, 1940 (Cl. 12 g-4.01). Chem. Abs., vol. 35, 1941, p. 4926.

Very effective catalysts are produced by converting thio salts, such as the S compounds of Cu, Zn, Sb, As, Mo, W, Cr, Re, Ge, with heavy metal compounds, such as halides, sulfates, nitrates, carbonates. The conversion can take place in aqueous or preferably organic solutions or suspensions. The 2 participitating metals should preferably be different. Good solvents that can be used are acid amides, for example, formamide, acid chlorides, for example, acetyl chloride, amino acids, ketonic acids, esters, nitriles, amines, aldehydes, ketones, or nitro compounds. In an example, 0.5 mol. TiCl₄ in C₆H₆ is slowly added to 1 mol. NH₄ thiotungstate in cyclohexylamine, while cooled by H₂O. The brown precipitate is filtered, and the solvents adhering to it are extracted with low-boiling solvents, for example, acetone or alcohol. It is then treated with H₂ with a slight admixture of H₂S at 300°-400°. The resulting gray-black compound is pressed and used.