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:
Mar. 13, 1990
Filed:
Jul. 21, 1987
Steven I Boldish, Plano, TX (US);
Irfan A Toor, Plano, TX (US);
Ethyl Corporation, Richmond, VA (US);
Abstract
A method and apparatus are described for removing arsine from a gaseous stream such as the gaseous effluent stream from an MOCVD operation in which arsine is employed as an arsenic source. The arsine is burned in the gas phase in the presence of oxygen (air) to form arsenic oxide and a gaseous effluent stream in which all or part of the arsenic oxide is entrained. The arsenic oxide is removed from this stream by washing the same with an aqueous stream thereby forming an aqueous solution of arsenic oxide. At least a portion of this aqueous solution is recirculated to the aqueous spray so that a progressively enriched aqueous solution of arsenic oxide is formed. Periodically an insoluble arsenic containing compound is precipitated from the solution before it becomes saturated with arsenic oxide. Thus, arsine is eliminated from gaseous streams and converted into harmless forms which can be readily handled and disposed of without harm to the environment. At the same time water requirements in the system are kept at a minimum and waste of this resource is reduced.