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:
Oct. 25, 1988
Filed:
Feb. 03, 1987
Applicant:
Inventors:
Gunther Schimmel, Erftstadt, DE;
Friedrich Kolkmann, Bruhl, DE;
Reinhard Gradl, Erftstadt, DE;
Herbert Ressel, Erftstadt, DE;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01B / ; C01B / ;
U.S. Cl.
CPC ...
4233 / ; 423220 ; 423317 ; 423320 ;
Abstract
Crude phosphoric acid is made by subjecting crude phosphate ore containing sulfide to processing treatment with a mineral acid in a closed system comprised of a processing reactor, a filtering zone and an off-gas scrubbing zone. To this end, a soluble compound of a metal forming difficultly soluble sulfides in the respective acid medium is added either