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:
Apr. 25, 1995
Filed:
Jan. 29, 1993
Wayne D Wimbish, St. Charles, MO (US);
Richard C Hallcher, Maryland Heights, MO (US);
Monsanto Company, St. Louis, MO (US);
Abstract
Apparatus and methods for removing silver and copper ions from purge streams from silver replacement processes by separately electrowinning silver and copper where silver removal is first effected in an electrowinning cell having a cathode/calomel reference electrode potential between -0.1 and -0.4 volts DC followed by copper removal effected in an electrowinning cell having a cathode/calomel reference electrode potential less than -0.5 volts DC. By this method formation of copper (+1) is prevented in the presence of high concentrations of silver, thus minimizing precipitation of silver metal and formation of copper (+2).