Douglas G Frick

US Patent:

41622952, Jul 24, 1979

Filed:

Nov 14, 1977

Appl. No.:

5/851230

Inventors:

Somanahalli N. Subbanna - Camillus NY
Thomas R. Morgan - Solvay NY
Douglas G. Frick - La Fayette NY

Assignee:

Allied Chemical Corporation - Morristown NJ

International Classification:

C01G 3714

US Classification:

423 61

Abstract:

A method for producing alkali metal chromates by double roasting chrome ores without the use of alkaline earths is disclosed. The pollution and hygiene problems associated with the use of lime are substantially eliminated and only negligible amounts of alumina are found in the product chromate liquors without employing steps previously thought necessary. These advantages are achieved by controlling (1) the Bichromate Equivalent: aluminum oxide ratio in the mix, (2) the amount of alkali metal salts added to the mix, (3) the roasting time, (4) the composition and alkalinity of the liquor used for leaching the roast, and (5) the temperature employed, in both roasts.

US Patent:

42449251, Jan 13, 1981

Filed:

Jul 20, 1979

Appl. No.:

6/058975

Inventors:

Somanahalli N. Subbanna - Camillus NY
Thomas R. Morgan - Solvay NY
Douglas G. Frick - La Fayette NY

Assignee:

Allied Chemical Corporation - Morris Township, Morris County NJ

International Classification:

C01G 3714
C01G 3100

US Classification:

423 61

Abstract:

A method for producing alkali metal chromates by a single roast of chrome ores without the use of calcium oxide is disclosed. A double roast embodiment is also contemplated for obtainment of enhanced yields. The pollution and hygiene problems associated with the use of lime are substantially eliminated and only negligible amounts of alumina are found in the product chromate liquors without employing steps previously thought necessary. These advantages are achieved by controlling (1) the Bichromate Equivalent: aluminum oxide ratio in the mix, (2) the amount of alkali metal salts added to the mix, (3) the roasting time, (4) the composition and alkalinity of the liquor used for leaching the roast, and (5) the temperature employed. Recovery of vanadium values from the alkali metal chromate liquors is also disclosed.