Tosoh Corporation

Hiroshima University

Yasuyuki Takamitsu

Tomoya Ishikawa

Mitsuaki Yoshimitsu

Hidekazu Aoyama

Yukio Ito

Satoshi Yoshida

Seiji Maehama

Takayoshi Mishima

Masahiro Sadakane

Tsuneji Sano

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.

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.

Provided is AEI zeolite having a uniform acid strength of an appropriate degree. AEI zeolite comprising phosphorus, preferably AEI zeolite comprising phosphorus in the pores, and a method for producing AEI zeolite comprising a crystallization step of crystallizing a raw material mixture containing a tetraethylphosphonium cation.

AEI zeolite containing phosphorus and production method therefor

A novel MFI zeolite that when used as a catalyst, can be used for a selective catalytic reaction for larger molecules and provides a method for producing the MFI zeolite. The MFI zeolite includes uniform mesopores having a pore distribution curve which a peak-width thereof at half height (hw) is at most 20 nm (hw&#x2266;20 nm) and a center value (&#x3bc;) of a maximum peak is 10 nm or more and 20 nm or less (10 nm&#x2266;&#x3bc;&#x2266;20 nm), and having a pore volume (pv) of the uniform mesopores of at least 0.05 mL/g (0.05 mL/g&#x2266;pv); the MFI zeolite has no peak in a range of 0.1&#xb0; to 3&#xb0; in powder X-ray diffraction measurement with a diffraction angle represented by 2&#x3b8;; and the MFI zeolite has an average particle diameter (PD) of at most 100 nm (PD&#x2266;100 nm).

MFI zeolite having uniform mesopores and method for producing same

A subject for the invention is to provide a highly heat-resistant SCR catalyst which has an NOx reduction percentage of 40% or higher at 200&#xb0; C. after a hydrothermal durability treatment. The invention relates to use of &#x3b2;-type zeolite which has an SiO/AlOmolar ratio of 20 or higher but less than 30 and a crystallite diameter before a hydrothermal durability treatment of 20 nm or larger, shows a change in crystallite through the hydrothermal durability treatment of less than 10%, and has a fluorine content lower than 0.1%. The &#x3b2;-type zeolite can be crystallized from a liquid reaction mixture containing a secondary and/or a tertiary alkylamine having 5 or more carbon atoms.

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Yamaguchi, Japan

Yasuyuki Takamitsu