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. 28, 1998
Filed:
Dec. 16, 1994
Applicant:
Inventors:
William E Fristad, Santa Rosa, CA (US);
Michael J Virnig, Santa Rosa, CA (US);
Jonathan M Cassel, Half Moon Bay, CA (US);
Assignee:
Henkel Corporation, Plymouth Meeting, PA (US);
Primary Examiner:
Int. Cl.
CPC ...
C22B / ; C22B / ;
U.S. Cl.
CPC ...
423-1 ; 423 98 ; 423109 ; 4236585 ;
Abstract
Heavy metals are efficiently removed from contaminated soil by a process which comprises leaching or washing the soil with a mild leachant solution. The leachant solution is comprised of an aqueous solution of an acid and a salt. The anion of the acid forms a water-soluble salt with the heavy metals which contaminate the soil. The salt component is comprised of at least one alkali metal, alkaline earth metal, or an ammonium salt having one or more anions which also form a water-soluble salt with the heavy metals leached from the contaminated soil.