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:
Dec. 17, 1996
Filed:
Mar. 02, 1995
Elkem a/s, , NO;
Abstract
The present invention relates to a method for recovering iron chloride, aluminum chloride and calcium chloride from silicon and ferrosilicon or from residues which contain silicon and/or ferrosilicon and metal chlorides and optionally copper and/or copper compounds, which materials are leached with HCl or HCl+FeCl.sub.3 /FeCl.sub.2 solutions, whereafter the solid silicon or ferrosilicon residue is removed from the leach solution and where any copper is removed from the leach solution. Fe.sup.2+ in the leach solution is oxidized to Fe.sup.3+ whereafter the leach solution is subjected to a liquid-liquid extraction by means of an organic phase containing n-tributyl phosphate dissolved in a hydrocarbon solvent in order to extract FeCl.sub.3 and at least a part of CaCl.sub.2 from the leach solution, stripping FeCl.sub.3 and any CaCl.sub.2 from the organic phase by water, concentrating the remaining solution by evaporation and adding HCl gas to the solution in order to selectively precipitate AlCl.sub.3.6H.sub.2 O from the solution and recovering AlCl.sub.3.6H.sub.2 O from the solution by filtration.