Patent Number: 7,465,429

Title: Heat-treated active carbons for use in denitration, processes for producing same, denitration method using same, and denitration system using same

Abstract: This invention relates to a technique for removing nitrogen oxides (NO.sub.x) present in exhaust gases discharged from boilers and the like. When the temperature of the exhaust gas is 100.degree. C. or below, a heat-treated active carbon produced by heat-treating a raw active carbon at 600 to 1,200.degree. C. in a non-oxidizing atmosphere so as to remove oxygen-containing functional groups present at the surfaces thereof and thereby reduce the atomic surface oxygen/surface carbon ratio to 0.05 or less is preferably used. When the temperature of the exhaust gas exceeds 100.degree. C., a heat-treated active carbon produced by heat-treating a raw active carbon at 600. to 1,200.degree. C. in a non-oxidizing atmosphere and activating the surfaces thereof with sulfuric acid or nitric acid to impart oxidizing oxygen-containing functional groups thereto is preferably used.

Inventors: Mochida; Isao (Fukuoka, JP), Yasutake; Akinori (Nagasaki, JP), Setoguchi; Toshihiko (Nagasaki, JP), Kobayashi; Norihisa (Chiyoda-ku, JP), Kasuh; Takahiro (Osaka, JP), Yoshikawa; Masaaki (Osaka, JP)

Assignee: Osaka Gas Company Limited

International Classification: B01J 8/02 (20060101)

Expiration Date: 2021-12-16 0:00:00