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, 1994
Filed:
Feb. 16, 1993
Applicant:
Inventor:
Roderick O McElroy, Vancouver, CA;
Assignee:
Terra Gaia Environmental Group Inc., Vancouver, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C22B / ;
U.S. Cl.
CPC ...
75725 ; 75961 ; 204118 ; 204128 ; 423 94 ; 423100 ; 423140 ; 423141 ;
Abstract
In a process for the treatment of electric arc furnace (EAF) dust, the dust is first subjected to atmospheric leaching with a ferric chloride solution and thereafter subjected to treatment in an autoclave at an elevated temperature and pressure for conversion of low temperature stable goethite (FeO.OH) to a filterable crystalline hematite (Fe.sub.2 O.sub.3) in an acidic chloride solution. Zinc is recovered from the solution by solvent extraction using a solvating extractant followed by stripping and zinc recovery by electrolysis of zinc chloride solution. Lead is separated from the solution by cooling to precipitate lead chloride.