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:
Jul. 28, 1998
Filed:
Oct. 28, 1997
Thomas L Varner, Jr, Wilmington, IL (US);
William C Hiatt, Hendersonville, NC (US);
Thomas A Hoermann, Toledo, OH (US);
BASF Corporation, Mt. Olive, NJ (US);
Abstract
Methods of removing contaminant metals from aqueous waste streams. A preferred method includes providing an aqueous waste stream containing a metal having a valence of at least one, such as zinc, lead, chromium, copper, iron, aluminum, manganese, cadmium, gold, silver, and mixtures of these metals. The waste stream is substantially free of calcium and magnesium. The process also includes forming a substantially insoluble precipitate of said metal by mixing with the waste stream fatty acids; zinc, potassium, and sodium salts of fatty acids; and mixtures of these materials. The metal precipitate is separated from the waste stream and the water that is subject to the removal process remains substantially free of calcium and magnesium throughout the entire process. The methods of the present invention are particularly effective for the removal of trace amounts of zinc from aqueous waste streams from polystyrene processes.