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:
May. 19, 1998
Filed:
Dec. 10, 1996
George E Gantt, Milledgeville, GA (US);
Gerald Smith, Dublin, GA (US);
Engelhard Corporation, Iselin, NJ (US);
Abstract
An improved method for improving the brightness of clay of the type that is capable of being bleached by an oxidative reagent, such as Georgia gray kaolin. Such clay, in the form of a dispersed slurry, is treated with a combination of an inorganic condensed phosphate, sodium hypochlorite and ozone, preferably including separate treatment steps of magnetic purification and reductive bleaching. Suitable phosphates include sodium hexametaphosphate, sodium tripolyphosphate and tetrasodium pyrophosphate. The hypochlorite is added shortly before ozonation, and the phosphate is added before, simultaneously with, or after the hypochlorite.