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. 07, 1982
Filed:
Nov. 28, 1980
Vladimir N Abrjutin, Moscow, SU;
Vyacheslav P Ezhkov, Svetlovodsk Kirovogradskoi oblasti, SU;
Raisa V Ivanova, Moscow, SU;
Oleg N Kalashnik, Svetlovodsk Kirovogradskoi oblasti, SU;
Vyacheslav A Kirichenko, Svetlovodsk Kirovogradskoi oblasti, SU;
Alexandr V Peredereev, Moscow, SU;
Jury G Pukhov, Svetlovodsk Kirovogradskoi oblasti, SU;
Arkady A Belsky, Moscow, SU;
Vladimir V Kozhemyakin, Ivanteevka Moskovskoi oblasti, SU;
Galina E Masjuk, Svetlovodsk Kirovogradskoi oblasti, SU;
Other;
Abstract
A process for producing high-purity gallium from gallium-arsenic containing wastes resulting from the manufacture of semiconductors which comprises a vacuum-thermal decomposition of said wastes under a residual pressure of from 1.10.sup.-1 to 1.10.sup.-2 mm Hg while elevating temperature to from 25.degree. to 1,150.degree. C. at variable heating rates ranging from 0.5.degree. to 20.degree. C./min. The vacuum-thermal decomposition of the wastes is accompanied by sublimation of arsenic which is condensed. The resulting melt of gallium is cooled to a temperature of from 50.degree. to 100.degree. C. at variable cooling rates ranging from 0.05.degree. to 15.degree. C./min. Then the melt of gallium is filtered at the cooling temperature of the melt. The filtered gallium melt is subjected to a hydrochemical treatment. The melt of gallium having passed the hydrochemical treatment is subjected to a fractional multi-stage crystallization to crystallize gallium in an amount of from 60 to 95% by mass of its initial charge in each stage; the metal residues enriched with impurities are recycled from each subsequent stage to each preceding one.