US 2016/0101415 A1 · ORGANIC-FREE SYNTHESIS OF SMALL PORE ZEOLITE CATALYSTS

Abstract

The present invention is directed to methods of enhancing the catalytic activities of 8-MR zeolites, the methods comprising treating a precursor 8-MR zeolite that has been prepared without the use of an organic structure directing agent and having an Si/Al ratio of less than 5, with high temperature steam for a period of time sufficient to extract at least a portion of the aluminum from the precursor zeolite framework to form a steam-treated zeolite having an Si/tetrahedral Al ratio of greater than 5, wherein the steam has a temperature in a range of from about 350° C. to about 850° C. The compositions produced by these methods and their use in catalytic reactions are also provided.

Claims22

Dependent claims

A method for improving the catalytic activity of a 8-MR zeolite, the method comprising treating the precursor 8-MR zeolite, prepared in the absence of any organic structure directing agent and having an Si/Al atom ratio of less than 5, with high temperature steam for a period of time sufficient to extract at least a portion of the aluminum from the precursor zeolite framework to form a steam-treated zeolite, wherein the steam has a temperature in a range of from about 350° C. to about 850° C.

A crystalline aluminosilicate composition containing an 8-MR zeolite structure, the composition characterized by two or more of:

(a) an atomic ratio of the silicon to tetrahedral aluminum atoms greater than 5;
(b) an atomic ratio of tetrahedral to total aluminum atoms in a range of from about 0.12 to about 0.6;
(c) a microporous region and a mesoporous region, in which the microporous region comprises tetrahedral aluminum and the mesoporous region contains tetrahedral, pentacoordinate, and/or hexacoordinate aluminum;
(d) a micropore volume comprising from 0.03 to 0.8 cc/gram of the composition;
(e) a total Brønsted acid site density in a range of from 0.6 to 1.2, preferably 0.7 to 0.9 mmol/gram of the composition, as determined by ammonia temperature-programmed desorption;
or
(f) a mesoporous Brønsted acid site density in a range of from 0.1 to 4 mmol/gram of the composition, as determined by isopropylamine temperature-programmed desorption.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application

14/882,587Filed 14 Oct 2015

Priority

14 Oct 2014

Published

14 Apr 2016

Term ends

Not estimatedThe source records don’t support an estimate.

Classification24 codes

B01J 37/10
Heat treatment: in the presence of water, e.g. steam
B01J 29/084
Of the faujasite type, e.g. type X or Y: y-type faujasite
B01J 29/70
Crystalline aluminosilicate zeolites; Isomorphous compounds thereof: of types characterised by their specific structure not provided for in groups…
B01J 29/7015
Of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65: cHA-type, e.g. Chabazite, LZ-218

Organic-free synthesis of small pore zeolite catalysts

Life of this patent

Organic-free synthesis of small pore zeolite catalysts

Life of this patent

Abstract

Claims22