The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 19, 1985
Filed:
May. 17, 1982
Elie M Chemtob, Claremont, CA (US);
Gary L Beer, Huntington Beach, CA (US);
Occidental Research Corporation, Los Angeles, CA (US);
Abstract
Substantially calcium-free fluoroaluminum phosphate precipitate (which also contains iron) can be produced by the aging of wet process phosphoric acid containing iron, fluorine and aluminum, preferably phosphoric acid analyzing in the range of about 15%-45 weight percent P.sub.2 O.sub.5, 2-4% Al.sub.2 O.sub.3 and 1-2% fluorine. One process involves digestion of phosphate ore matrix in recycled phosphoric acid, filtration to remove the insoluble residue, precipitation and filtration to remove gypsum, and aging of the product acid to precipitate the aluminum impurity as a fluoroaluminum phosphate compound. The fluoroaluminum phosphate can be decomposed (as by heating at about 195.degree. C.) to produce HF and aluminum phosphate.