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. 13, 1991
Filed:
Oct. 27, 1989
Ralf Kehl, Duesseldorf, DE;
Werner Schwab, Langenfeld, DE;
Robert B Sudderth, Tucson, AZ (US);
Gary A Korkosky, Tucson, AZ (US);
Henkel Kommanditgesellschaft auf Aktien, Duesseldorf-Holthausen, DE;
Abstract
Prior art processes for removal of one or more contaminant elements, including at least one of antimony, bismuth, and arsenic and optionally including iron, from electrolyte solutions of primary metals by solvent extraction with an organic phase including a hydroxamic acid, then precipitating at least part of the contaminant elements from the organic phase as sulfides, are improved by an additional step of re-extracting the organic phase with water before precipitating the sulfides from it. At least part of any arsenic present and, if desired, part of any antimony as well, may be re-extracted in this manner and subsequently recovered if desired, so that the overall process is made more economical.