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:
Aug. 09, 1988
Filed:
Apr. 16, 1987
Applicant:
Inventors:
Assignee:
Hoechst Aktiengesellschaft, Hurth Knapsack, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01B / ;
U.S. Cl.
CPC ...
4233 / ; 4236585 ; 210634 ; 210688 ;
Abstract
Residue obtained upon the removal of heavy metal contaminants from crude phosphoric acid by means of a dialkyldithiophosphoric acid ester and adsorbent is worked up into ecologically reliable solid matter and into a heavy metal concentrate. The solid matter and heavy metal concentrate are separated from one another by successive mechanical and chemical treatment. The sequential order of these two operational steps can be inversed.