Tosoh Corporation

Hidekazu Aoyama

Ko Ariga

Seiji Maehama

Satoshi Nakamura

Kazuhiko Sekizawa

Senshi Kasahara

Hiroshi Miura

Yusuke Naraki

Tomoya Ishikawa

Takayoshi Mishima

Keisuke Tokunaga

Keita Nakao

Hiroshi Ogawa

Yasuyuki Takamitsu

Mitsuaki Yoshimitsu

Yuuki Ito

Hiroshi Okaniwa

Kou Ariga

Shoji Adachi

A CHA-type zeolite has a molar ratio of silica to alumina of 10.0 or more and less than 20.0 and a molar ratio of silanol groups to silicon of 0.15&#xd7;10or more and 0.50&#xd7;10or less, a molar ratio of silica to alumina of 20.0 or more and 35.0 or less and a molar ratio of silanol groups to silicon of 0.15&#xd7;10or more and 1.10&#xd7;10or less, a molar ratio of silica to alumina of more than 35.0 and 45.0 or less and a molar ratio of silanol groups to silicon of 0.15&#xd7;10or more and 1.65&#xd7;10or less, or a molar ratio of silica to alumina of more than 45.0 and 55.0 or less and a molar ratio of silanol groups to silicon of 0.15&#xd7;10or more and 1.80&#xd7;10or less.

CHA-type zeolite and method for producing the same

Provided is a metal-containing CHA-type zeolite in which a ratio of a maximum intensity of an absorption peak in a range of 3685 cmor more and 3750 cmor less to a maximum intensity of an absorption peak in a range of 1800 cmor more and 1930 cmor less is less than 1.5 in an IR spectrum. A method for producing the metal-containing CHA-type zeolite includes a metal incorporation step of mixing a metal source and a CHA-type zeolite in which a ratio of a maximum intensity of an absorption peak in a range of 3665 cmor more and 3750 cmor less to a maximum intensity of an absorption peak in a range of 1800 cmor more and 1930 cmor less is less than 1.5 in an IR spectrum.

Metal-containing cha-type zeolite and method for producing the same

Provided is a production method by which an AEI zeolite is obtained without inducing a structural transformation in a crystalline aluminosilicate having a Y-structure and without using fluorine or phosphorus, the method including a crystallization step of crystallizing a composition containing an alumina source, a silica source, a structure directing aunt, a sodium source, and water, a weight proportion of crystalline aluminosilicate relative to a total weight of the alumina source and the silica source being from 0 wt. % to 10 wt. %, and the crystallization step satisfying at least one of the following conditions: a molar ratio of hydroxide ion to silica in the composition is 0.45 or greater, the composition contains a cation represented by (CH)RN(R represents an alkyl group having from 1 to 4 carbons, and the alkyl group may contain at least one substituent), and the crystallization time is 80 hours or longer.

Method for producing AEI zeolite

Provided is a production method by which an AEI zeolite is obtained without inducing a structural transformation in a crystalline aluminosilicate having a Y-structure and without using fluorine or phosphorus, the method including a crystallization step of crystallizing a composition containing an alumina source, a silica source, a structure directing agent, a sodium source, and water, a weight proportion of crystalline aluminosilicate relative to a total weight of the alumina source and the silica source being from 0 wt. % to 10 wt. %, and the crystallization step satisfying at least one of the following conditions: a molar ratio of hydroxide ion to silica in the composition is 0.45 or greater, the composition contains a cation represented by (CH)RN(R represents an alkyl group having from 1 to 4 carbons, and the alkyl group may contain at least one substituent), and the crystallization time is 80 hours or longer.

A process of manufacturing a chabazite-type zeolite is provided having high heat resistance without having a large crystal size. A catalyst is also provided that contains such a chabazite-type zeolite and exhibits high nitrogen oxide reduction properties, and in particular high nitrogen oxide reduction properties in low temperatures below 200&#xb0; C., even after exposure to high temperature and high humidity. A chabazite-type zeolite is provided having a silica to alumina molar ratio of no less than 15, a silanol group to silicon molar ratio of no more than 1.6&#xd7;10, an average crystal size of 0.5 &#x3bc;m to less than 1.5 &#x3bc;m, and a ratio of 50%-volume particle size to 10%-volume particle size of no more than 3.2. The chabazite-type zeolite preferably contains at least one of copper and iron.

Chabazite-type zeolite and method of manufacturing chabazite-type zeolite

A subject for the invention is to provide a chabazite-type zeolite that is expected to have durability and thermal resistance, which are practical properties required of catalyst supports and adsorbent bases, and that has profitability. A chabazite-type zeolite having an SiO/AlOmolar ratio of 15-50 and an average particle diameter size of 1.5 &#x3bc;m or more has high durability and high thermal resistance. Such a chabazite-type zeolite can be produced by crystallizing a starting-material composition in which the molar ratios of a structure-directing agent and water to SiOsatisfy0.05&#x2264;(structure-directing agent)/SiO&#x3c;0.13 and5&#x2264;HO/SiO&#x3c;30,in the presence of at least one kind of alkali metal ions selected from the group consisting of K, Rb, and Cs. The structure-directing agent preferably is an N,N,N-trimethyladamantaneammonium salt.

Chabazite-type zeolite and process for producing the same

The chabazite-type zeolite of the present invention has a SiO/AlOmolar ratio of less than 15, and an average particle size from 1.0 &#x3bc;m to 8.0 &#x3bc;m. The chabazite-type zeolite of the present invention has excellent durability and heat resistance, and the copper-loaded chabazite-type zeolite has an improved NOx reduction rate at low temperatures compared to conventional copper-loaded chabazite-type zeolite.

Chabazite-type zeolite and method for producing same, copper loaded low-silica zeolite and NOx reductive removal catalyst containing the zeolite, and method of NOx reductive removal using this catalyst

The present invention relates to a silicoaluminophosphate represented by the following formula (1) and having a powder X-ray diffraction pattern shown in Table 1 below:(SiAlP)O&#x2003;&#x2003;(1)wherein x is the molar fraction of Si and 0.05&#x3c;x&#x2266;0.15; y is the molar fraction of Al and 0.47&#x2266;y&#x2266;0.52; z is the molar fraction of P and 0.40&#x2266;z&#x2266;0.46; and x+y+z=1; 

Silicoaluminophosphate, method for producing the same, and solid acid catalyst comprising the same

An SCR catalyst using a &#x3b2;-zeolite in which the molar ratio of SiO/AlOis from 20 to less than 40, the particle diameter determined by SEM is 0.35 &#x3bc;m or more, the full width at half maximum (FWHM) of the X-ray diffraction peak for (302) is less than 0.30&#xb0;, and the amount of adsorbed NHis 1 mmol/g or more, or has an amount of adsorbed NHfollowing hydrothermal aging of 0.4 mmol/g or more, demonstrates high catalytic activity for NOx reduction at low temperatures following hydrothermal aging while also demonstrating a low level of discharge of irritating ammonia in exhaust gas.

&#x3b2;-Zeolite for SCR catalyst and method for purifying nitrogen oxides using same

A first catalyst for reducing nitrogen oxides comprising a crystalline silicate containing an iron in &#x3b2;-framework structure wherein a SiO/FeOmol ratio is 20-300 and at least 80% of the contained iron is an isolated iron ion Fe. A second catalyst for reducing nitrogen oxides comprising a crystalline silicate containing an iron in &#x3b2;-framework structure wherein a SiO/FeOmol ratio is 20-300 and log(SiO/AlO) by mol is at least 2. A predominant part of the contained iron is isolated iron ion Feand at least a part thereof preferably has a tetrahedral coordination. These catalysts have high hydrothermal stability and exhibit enhanced activity for reducing nitrogen oxides by a reaction with a reducing agent such as ammonia, urea or an organic amine in a broad temperature range between lower temperature and higher temperature.

Nitrogen oxide-reducing catalyst and method for reducing nitrogen oxide

A method for removing nitrogen oxides from an oxygen-rich exhaust gas containing nitrogen oxides and hydrocarbons comprising bringing the oxygen-rich exhaust gas into contact with a catalyst comprising (1)(i) a zeolite containing an apatite compound and having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of at least 15 and (ii) at least one active metal or (2)(ii) a zeolite containing an apatite compound and having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of at least 15, (ii) an alkaline earth metal and (iii) at least one active metal.

Method for removal of nitrogen oxides

Nitrogen oxides are removed from an oxygen rich exhaust gas containing nitrogen oxides and hydrocarbons by bringing the oxygen rich exhaust gas into contact with a catalyst composed of phosphorus and at least one active metal contained in a zeolite having a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of at least 15.

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Yamaguchi, Japan

Hidekazu Aoyama