Tosoh Corporation

Tomoya Ishikawa

Hidekazu Aoyama

Yasuyuki Takamitsu

Mitsuaki Yoshimitsu

Takayoshi Mishima

Yoshitaka Yamasaki

Yusuke Naraki

Keita Nakao

Seiji Maehama

Takuya Okada

Provided is at least one of a production method that can obtain AEI zeolite that has a silica-to-alumina molar ratio suitable as a nitrogen oxide-reducing catalyst or a support thereof and that involves a shorter crystallization time and higher yield compared to a typical AEI zeolite production method that does not use crystalline aluminosilicate as a starting material, or an AEI zeolite production method that is expected to be industrially applicable. An AEI zeolite production method includes hydrothermally processing an amorphous composition containing an amorphous silica source, an amorphous alumina source, an alkali source and water, and then crystallizing a raw material composition obtained by mixing an organic structure-directing agent and the amorphous composition.

Method for producing AEI zeolite

CHA-type zeolite in which the molar ratio of silica to alumina is less than 13, and the content of sodium is 100 ppm or more and 2000 ppm or less is provided. Such a CHA-type zeolite is obtained by a manufacturing method including obtaining a crystallized product by crystallizing a composition which includes a structure-directing agent source containing at least N,N,N-trialkylcyclohexylammonium cation, an alumina source, a silica source, a sodium source, and water and in which the molar ratio of silica to alumina is 20 or less and in which the molar ratio of potassium to sodium is less than 0.05, removing N,N,N-trialkylcyclohexylammonium cation from the crystallized product, and contacting the crystallized product with an ammonium-salt-containing solution having an ammonium concentration of 1 mass percent or more.

CHA-type zeolite and manufacturing method thereof

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.

Provided is a method for producing an AEI zeolite without the use of a zeolite Y and a raw material containing fluorine and phosphorus, the method including a crystallization step of crystallizing a composition containing a structure directing agent, a sodium source, water, and a zeolite having at least one of the following structures as a silica alumina source.

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.

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Yamaguchi, Japan

Tomoya Ishikawa