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:
Jan. 08, 1980
Filed:
Oct. 17, 1977
Fusao Nishida, Tokyo, JP;
Toshihiro Ueno, Yokohama, JP;
Tomiaki Yamada, Yokohama, JP;
Noriyuki Suzuki, Tokyo, JP;
Takehiko Takeda, Yokohama, JP;
Tsutomu Yanagihara, Tokyo, JP;
Katsuhiko Adachi, Yokohama, JP;
Tadashi Asanabe, Zushi, JP;
Katsuaki Ohsato, Yokohama, JP;
Kintaro Tsuda, Tokyo, JP;
Keiichiro Watanabe, Yokohama, JP;
JGC Corporation, Tokyo, JP;
Abstract
The present invention relates to a catalyst comprising at least a metal salt of heteropoly-acid, which is composed of a sort of heteropoly-acid and one or more metals selected from a group of the first transition metals of the periodic table. The catalyst of the present invention exhibits high activity and selectivity in the catalytic reduction of nitrogen oxides with ammonia at a temperature of from 250.degree. to 550.degree. C. and offers high resistivity to the poisonous effect of sulfur oxides. It does not entail a wasteful use of the reducing agent, because the catalyst of the present invention does not accelerate the reaction of the reducing agent such as ammonia with oxygen coexisting in the waste gas to be treated, which results in the elimination of the undesired excessive consumption of the reducing agent. Therefore, this invented catalyst may provide a commercially advantageous process for removing harmful constituents, nitrogen oxides from a waste gas which contains the same and additionally, in some cases, sulfur dioxides.