Sakai Chemical Industry Co., Ltd.

Mitsubishi Jukogyo Kabushiki Kaisha

Mitsubishi Petrochemical Company Limited

Other

Catalysts & Chemicals Industries Co., Ltd.

Mitsubishi Jukogyo K.k.

Mitsubishi Petrochemical Engineering Co., Ltd.

Catalysts & Chemical Co., Ltd.

Hiroaki Rikimaru

Toshikatsu Umaba

Tadao Nakatsuji

Hiromitsu Shimizu

Kazunobu Abe

Kazuya Mishina

Hiroshi Hasegawa

Norihisa Kobayashi

Kozo Iida

Shigeaki Mitsuoka

Makoto Imanari

Kazuhiko Nagano

Atsushi Morii

Touru Seto

Morio Fukuda

Toshio Koyanagi

Masayuki Hanada

Akihiro Yamauchi

Kiyoshi Nagano

Takeo Koshikawa

Kazuhisa Hidaka

Masashi Aoki

Iwao Yamazaki

Hiromu Takatsuka

Yoshiyuki Yoshikawa

Takeshi Ito

Kayoko Segawa

Masaki Miyazawa

Kuzuhiko Nagano

A catalyst for reducing nitrogen oxides into nitrogen and water in the presence of a reducing agent, which comprises:

Catalyst and method for denitrization of nitrogen oxides

A catalyst for denitrizing nitrogen oxides contained in waste gases in the presence of arsenic compounds, which comprises: titanium and vanadium therein in weight ratios of oxides of titanium to oxides of vanadium ranging from 99.9:0.1 to 92.0:8.0, the vanadium being concentratedly contained in the surface layer of the catalyst up to 200 .mu.m in depth from the surface of the catalyst in concentrations of at least about 1.5 times as much as the concentrations of vanadium throughout the catalyst. The catalyst may further contain therein at least one of tungsten and zirconium. The catalyst preferably has micropores of about not less than about 50 .ANG. in amounts of 0.25-0.40 ml/g, and micropores of about 50-100 .ANG. in radius in amounts of about 10-40% by volume and micropores of about 1000-60000 .ANG. in radius in amounts of not less than about 10% by volume, respectively, based on the total volume of the micropores of not less than about 50.ANG. in radius. The catalyst retains a higher denitrizing activity over a long period of denitrizing operations in the presence of arsenic compounds contained waste gases than the conventional catalysts.

Catalyst for denitrizing nitrogen oxides contained in waste gases

Here is provided an adsorbent for adsorbing and removing an arsenic compound which becomes a catalyst poison in a selective contact reduction process for removing nitrogen oxides (NOx) from a combustion exhaust gas by the use of an ammonia as a reducing agent and a denitrating catalyst. The adsorbent of the present invention comprises a material in which the total volume of pores is 0.2 to 0.7 cc/g and the volume of the pores having a pore diameter of 300 .ANG. or more is 10% or more with respect to the total pore volume, and the material is a specific element, its oxide, an ion-exchanged zeolite or the like. In addition, the present invention is directed to a method for removing the arsenic compound from the combustion exhaust gas by injecting the adsorbent into the flow of the gas on the upstream side of the denitrating catalyst.

Adsorbent for arsenic compound and method for removing arsenic compound

A catalyst for denitrizing nitrogen oxides contained in waste gases, which comprises:

Catalyst and a method for denitrizing nitrogen oxides contained in waste

A process for producing a composition which includes a perovskite compound, the process comprising:

Process for producing a composition which includes perovskite compounds

A process for preparing shaped catalysts or carriers mainly containing titanium oxide and improved in mechanical strength which comprises calcining a material mainly comprising titanium oxide or a substance convertible into titanium oxide on calcination in the presence of metatitanic acid sol or gel, said metatitanic acid sol being the one prepared by deflocculation of metatitanic acid obtained in the course of the production of titanium oxide according to a conventional sulfuric acid process and said metatitanic acid gel being the one prepared by adjusting said metatitanic acid sol to pH 1 or higher.

Production of shaped catalysts or carriers comprising titanium oxides

Growing community of inventors

Sakai, Japan

Hiroaki Rikimaru