Method for the preparation of a molecular sieve belonging to the ABC-6 framework family with disorder in the ABC stacking sequence

Patent metadata

Field	Value
Publication number	US-10919773-B2
Application number	US-201716335758-A
Country	US
Kind code	B2
Filing date	Nov 2, 2017
Priority date	Nov 10, 2016
Publication date	Feb 16, 2021
Grant date	Feb 16, 2021

Abstract

A method for the preparation of a molecular sieve belonging to the ABC-6 framework family with disorder in the ABC stacking sequence essentially composed of double-six-ring periodic building units and having a mole ratio of silicon oxide to aluminum oxide from about 8 to about 60.

First claim

The invention claimed is:

1. A method for the preparation of a molecular sieve belonging to the ABC-6 framework family with disorder in the ABC stacking sequence essentially composed of double-six-ring periodic building units and having a mole ratio of silicon oxide to aluminum oxide from about 8 to about 60, the method comprises the steps of:
i) preparing a synthesis mixture comprising at least one crystalline molecular sieve containing six-ring structural features, a source of alkali or earth alkali (A), at least one OSDA and water in molar ratios of:

SiO2/Al2O3
 8-60

OSDA/SiO2
0.01-1.0 

A/SiO2
0.01-1.0 

OH/SiO2
0.01-1.5 

H2O/SiO2
  2-200

ii) subjecting the mixture to conditions capable of crystallizing the molecular sieve; and
iii) separating the molecular sieve product;
wherein the at least one OSDA is a cation with the generic structure described as [NR 1 R 2 R 3 R 4 ] + , and wherein at least three of the R-groups are linear alkyl groups with one to four carbon atoms.

2. The method of claim 1 , wherein the molecular sieve product in its as-synthesized and anhydrous form has a composition expressed by the following molar ratios:

SiO2/Al2O3
 8-60

OSDA/SiO2
0.01-0.5 

A/SiO2
 0.01-0.5. 

3. The method of claim 1 , wherein the at least one OSDA is tetraethylammonium, methyltriethylammonium, propyltriethylammonium, diethyldipropylammonium, diethyldimethylammonium, choline cations and combinations thereof.

4. The method of claim 3 , wherein the at least one OSDA is tetraethylammonium cation.

5. The method of claim 1 , wherein the at least one crystalline molecular sieve containing six-ring structural features is selected from FAU, GME, LEV, AEI, LTA, OFF, CHA and ERI or mixtures thereof.

6. The method of claim 1 , wherein the synthesis mixture further comprises a source of silicon selected from the group consisting of: silica, fumed silica, silicic acid, silicates, colloidal silica, tetraalkyl orthosilicates and mixtures thereof.

7. The method of claim 1 , wherein the synthesis mixture further comprises a source of aluminum selected from the group consisting of: alumina, boehmite, aluminates and mixtures thereof.

8. The method of claim 1 , wherein the synthesis mixture further comprises sources of both silicon and aluminium selected from the group consisting of: precipitated silica-alumina, amorphous silica-alumina, kaolin, amorphous mesoporous materials and mixtures thereof.

9. The method according to claim 1 , wherein at least a part of the aluminum and/or silicon is substituted by one or more metals selected from tin, zirconium, titanium, hafnium, germanium, boron, iron, indium and gallium.

10. The method of claim 1 , wherein the synthesis mixture further comprises an amount of seed crystals of molecular sieves belonging to the ABC-6 framework family.

11. The method of claim 10 , wherein the seed crystals are selected from molecular sieves having the CHA, GME framework structures or belonging to the disordered CHA-GME series.

12. The method of claim 10 , wherein the amount of seed crystals corresponds to 0.1 to 25% based on the total amount of silica in the synthesis mixture.

13. The method of claim 1 , comprising the further step of removing the at least one OSDA from the molecular sieve product by calcination.

14. The method of claim 1 , comprising the further step of removing the alkali or earth alkali (A) from the molecular sieve product by ion-exchange with ammonium and/or hydrogen.

15. The method of claim 1 , comprising the further step of introducing metal ions into and/or on the molecular sieve product by a process selected from the group consisting of: ion-exchange, impregnation, solid-state procedures and precipitation on surface of the molecular sieve product.

16. The method according to claim 15 , wherein the metal ion is copper and/or iron.

17. The method according to claim 1 , wherein the as-synthesized form of the molecular sieve has a powder X-ray diffraction pattern collected in Bragg-Brentano geometry with a variable divergence slit using Cu K-alpha radiation essentially as shown in the following Table:

2-Theta (°)
d-spacing (Å)
Relative peak area
Peak character

7.45-7.54
11.85-11.72
W-M
Broad to sharp

9.55-9.65
9.24-9.15
VS-W
Sharp to broad

11.40-11.66
7.75-7.58
W-M
Broad to sharp

12.90-13.04
6.85-6.78
S-W
Sharp

14.07-14.21
6.29-6.23
M-W
Sharp to broad

14.89-15.12
5.94-5.85
W
Broad to sharp

16.08-16.27
5.50-5.44
VS-W
Sharp to broad

17.17-17.34
5.16-5.11
W-S
Broad to sharp

17.71-18.00
5.00-4.92
VS-S
Sharp

where the relative areas of the observed peaks in the 2-Theta

Assignees

• Haldor Topsoe As
• Umicore Ag & Co Kg

Inventors

• Vennestrøm Peter N R
• Lundegaard Lars Fahl
• Jensen Brian

Classifications

• C01B39/48 Primary

  using at least one organic template directing agent · CPC title

• B01J29/76

  Iron group metals or copper · CPC title

• C01B39/026

  After-treatment · CPC title

• B01J37/0246

  Coatings comprising a zeolite · CPC title

• B01J2229/186

  not in framework positions · CPC title