B-type iron silicate composition and method for reducing nitrogen oxides

Patent metadata

Field	Value
Publication number	US-9539565-B2
Application number	US-201214115379-A
Country	US
Kind code	B2
Filing date	May 17, 2012
Priority date	May 17, 2011
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

The present invention relates to a composition including a β-type iron silicate, which includes all or part of iron in a β-type framework structure, and a solid acidic porous inorganic oxide. The present invention is characterized in that the β-type iron silicate is compounded with the porous inorganic oxide having solid acidic properties so that the solid acidic function derived from aluminum of the β-type iron silicate, is reinforced or complemented by the porous inorganic oxide, the individual particles of which are physically isolated from each other. It is preferred that the fluorine content relative to the dry weight of the β-type iron silicate is 400 ppm or less and the crystal particles of the β-type iron silicate have a truncated square bipyramidal morphology. According to the present invention, a composition that is useful as a high-performance catalyst, adsorbent, or the like, can be provided.

First claim

The invention claimed is:

1. A composition comprising (i) a β-type iron silicate, which comprises all or part of iron in a β-type framework structure mixed with (ii) a solid acidic porous inorganic oxide.

2. The composition according to claim 1 , wherein
a fluorine content relative to a dry weight of (i) the β-type iron silicate is 400 ppm or less, and
crystal grains of (i) the β-type iron silicate have a truncated square bipyramidal morphology.

3. The composition according to claim 1 , wherein
a SiO 2 /Al 2 O 3 molar ratio of (i) the β-type iron silicate is 300 or more, and
an iron content relative to a dry weight of (i) the β-type iron silicate is 5.5% by weight or more and 12% by weight or less.

4. The composition according to claim 1 , wherein (ii) the porous inorganic oxide is at least one type of porous inorganic oxide selected from the group consisting of a zeolite, an alumina, and a silica-alumina compound or a composite oxide.

5. The composition according to claim 4 , wherein the zeolite has at least one type of crystalline structure selected from the group consisting of *BEA, FAU, MOR, MFI, FER, LTL, MWW, MTW, CHA, LEV, and SZR.

6. The composition according to claim 5 , wherein the zeolite is an H-type zeolite.

7. A nitrogen oxide-reducing catalyst comprising the composition according to claim 1 .

8. A method of reducing nitrogen oxides, comprising selectively reducing a nitrogen oxide by contacting the nitrogen oxide with at least one type of reducing agent selected from the group consisting of ammonia, urea, and an organic amine, under the presence of the nitrogen oxide-reducing catalyst according to claim 7 .

Assignees

• Naraki Yusuke
• Ariga Ko
• Tosoh Corp

Inventors

• Naraki Yusuke
• Ariga Ko

Classifications

• B01J29/7007

  Zeolite Beta · CPC title

• B01J29/7034

  MTW-type, e.g. ZSM-12, NU-13, TPZ-12 or Theta-3 · CPC title

• B01J29/08

  of the faujasite type, e.g. type X or Y · CPC title

• B01D2258/014

  Stoichiometric gasoline engines · CPC title

• B01J29/88 Primary

  Ferrosilicates; Ferroaluminosilicates {(B01J29/005 takes precedence)} · CPC title