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. 09, 1996
Filed:
Apr. 19, 1994
Lucky Metals Corporation, Seoul, KR;
Abstract
A method for the re-treatment of residue generated in the course of removing fluorine from waste water. The method comprises the step of: drying the residues consisting of rare earth fluorides, which are generated in the course of treating the waste water with a rare earth compound to remove fluorine ions from the waste water; mingling the rare earth fluorides with a sodium hydroxide solid; heat treating the rare earth fluorides at temperatures ranging from approximately 320.degree. to approximately 450 .degree. C. for times ranging from approximately 0.5 to approximately 5 hours; and applying wash and dry to the heat-treated resultant, in due order. The invention pertains to the reuse of rare earth elements used in the treatment of fluorine. Products obtained by carrying out the method contain rare earth hydroxides, which are useful as materials for glass abrasive or for treating fluorine, catalysts, and other materials for the fields of using a variety of rare earth.