1704. ------. [INTERNATIONAL HYDROCARBON SYNTHESIS CO.] Regeneration of Spent Cobalt Catalysts in the Synthesis of Hydrocarbons. British Patent 530,036, Dec. 3, 1940; appl. filed June 15, 1939. Chem. Abs., vol. 35, 1941, p. 8226.

PATENTS

1704. ------. [INTERNATIONAL HYDROCARBON SYNTHESIS CO.] Regeneration of Spent Catalysts in the Synthesis of Hydrocarbons. British Patent 530,036, Dec. 3, 1940; appl. filed June 15, 1939. Chem. Abs., vol. 35, 1941, p. 8226.

Spent catalyst containing Th is treated with a mineral acid to dissolve the Th and, if desired, the other catalyst constituents. A sludge is precipitated by Na₂CO₃ from the acid solution obtained. This sludge contains a large amount of Th. The sludge is dissolved in H₂SO₄. The Th is precipitated by K₂SO₄ from the H₂SO₄ solution obtained as Th-K sulfate, which in turn is separated from the solution. An insoluble Th (CO₃)₂ is prepared from the sulfate and the carbonate is recovered.