STA-20, a novel molecular sieve framework type, methods of preparation and use

Patent metadata

Field	Value
Publication number	US-10213776-B2
Application number	US-201715581092-A
Country	US
Kind code	B2
Filing date	Apr 28, 2017
Priority date	Apr 28, 2016
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

STA-20, a molecular sieve having a new framework type, is described. STA-20AP (as prepared) can have an alkyl amine, such as trimethylamine, and 1,6-(1,4-diazabicyclo[2.2.2]octane) hexyl cations (from diDABCO-C6) as SDAs. A lower alkyl ammonium hydroxide, such as tetrabutylammonium hydroxide, can be used as a pH modifier for making SAPO STA-20. A calcined product, STA-20C, formed from as made STA-20 is also described. Methods of preparing STA-20, activating STA-20 by calcination, and metal containing calcined counterparts of STA-20 are described along with methods of using STA-20 and metal containing calcined counterparts of STA-20 in a variety of processes, such as treating exhaust gases and converting methanol to olefins are described.

First claim

What is claimed is:

1. Molecular sieve STA-20 having a framework type the following information on the unit cell of calcined, dehydrated SAPO STA-20:

SAPO STA-20

calcined, dehydrated

Unit cell

Chemical formula
Al 36 Si 7.2 P 28.8 O 144

Crystal system
trigonal

Space group
P −3 1 c

a/Å
13.15935
(26)

b/Å
13.15935
(26)

c/Å
30.5837
(6)

Volume/Å 3
4586.58
(20)

2. The molecular sieve of claim 1 , wherein the molecular sieve is a silicoaluminophosphate, a metal silicoaluminophosphate or a metal aluminophosphate.

3. The molecular sieve of any claim 1 , where the molecular sieve is a silicoaluminophosphate.

4. The molecular sieve of claim 1 , where the STA-20 structure is free from structural faulting.

5. The molecular sieve of claim 1 , where the molecular sieve comprises at least one metal within the framework where the metal is selected from at least one of the metals of Groups of the Periodic Table IIIA, IB, IIB, VA, VIA, VIIA, VIIIA and combinations thereof.

6. The molecular sieve of claim 1 , where the molecular sieve further comprises at least one extra-framework transition metal selected from the group consisting of Ag, Ce, Co, Cr, Cu, Fe, Ga, In, Ir, Mn, Mo, Ni, Pd, Pt, Re, Rh, Ru, Sn and Zn.

7. The molecular sieve of claim 1 , where the molecular sieve is calcined or contains one of more structure directing agents.

8. The molecular sieve of any claim 1 , the molecular sieve having a molar relationship: (Si x Al y P z )O 2 , where x is the mole fraction of Si having a value from 0.01 to 0.3, y is the mole fraction of Al having a value from 0.4 to 0.6, z is the mole fraction of P having a value from 0.2 to 0.5, and x+y+z=1.

9. The molecular sieve of claim 8 , where the molecular sieve is a calcined molecular sieve and has a characteristic X-ray powder diffraction pattern comprising 2-theta positions at 7.9 (vs), 11.8 (vs), 13.7 (vs), 14.2 (vs) and 25.1 (vs)±0.2 with the corresponding relative intensity shown in parenthesis, where the corresponding relative intensities are W (weak)<20; M (medium) is ≥20 and <40; S (strong) is ≥40 and <60; and VS (very strong) is ≥60.

10. The molecular sieve of claim 1 , where the molecular sieve further comprises one or more structure directing agents.

11. The molecular sieve of claim 10 , where the structure directing agents comprises an alkyl amine and a 1,4-diazabicyclo[2.2.2]octane derivative.

12. The molecular sieve of claim 11 , where the alkyl amine is trimethylamine or dimethylethylamine.

13. The molecular sieve of claim 11 , where the 1,4-diazabicyclo[2.2.2]octane derivative comprises a 1,6-(1,4-diazabicyclo[2.2.2]octane)hexyl cation.

14. The molecular sieve of claim 11 , where the alkyl amine is trimethylamine or N,N-dimethylethylamine and the 1,4-diazabicyclo[2.2.2]octane derivative is a 1,6-(1,4-diazabicyclo[2.2.2]octane)hexyl cation, where the molecular sieve has a characteristic X-ray powder diffraction pattern comprising 2-theta positions at 7.7 (vs), 14.2 (s), 15.5 (s), 20.6 (s) and 25.1 (vs)±0.2 with the corresponding relative intensity shown in parenthesis, where the corresponding relative intensities are W (weak)<20; M (medium) is ≥20 and <40; S (strong) is ≥40 and <60; and VS (very strong) is ≥60.

15. A catalyst comprising an STA-20 molecular sieve of claim 1 .

16. The catalyst of claim 15 , wherein the molecular sieve comprises about 0.1 to about 5 weight percent of a transition metal or noble metal.

17. A catalyst article for treating exhaust gas comprising a catalyst composition of claim 15 , where the catalyst is disposed on and/or within a honeycomb structure.

18. A method for synthesizing a molecular sieve of claim 1 , the method comprising:
a. forming heating a reaction mixture comprising: (i) at least one source of alumina, (ii) at least one source of silica, (iii) at least one source of phosphorus, and (iv) one or more structure directing agents wherein the reaction mixture has a molar compositional ratio of:

P/A
 0.5-0.99

MeO 2/ A
0.02-1.0 

SDA1 (1,4-diazabicyclo[2.2.2]octane derivative)/A
0.1-0.6

SDA2 (lower alkylamine)/A
0.1-0.6

Lower alkyl ammonia hydroxide/A
0.1-0.6

H 2 O/A
 20-200

where P the source of phosphorous and is calculated as being in the oxide form (P 2 O 5 ), A is Al, Fe, Cr, B, Ga or combinations thereof and is calculated as being in the oxide form (A 2 O 3 ); and Me is Si, Ge, Mg or combinations thereof and is calculated as being in the oxide form (MeO 2 );
b. forming molecular sieve crystals having an STA-20 framework and the structure directing agent, and
c. recovering at least a portion of the molecular sieve crystals from the reaction mixture.

19. A method for treating an exhaust gas comprising contacting a combustion exhaust gas containing NO x and/or NH 3 with a catalyst of claim 1 to selectively reduce at least a portion of the NO x into N 2 and H 2 O and/or oxidize at least a portion of the NH 3 .

20. A method for treating an exhaust gas comprising contacting a combustion exhaust gas containing NO x with a passive NOx absorber comprising a molecular sieve of claim 1 .

Assignees

• Johnson Matthey Plc

Inventors

• Casci John
• Turrina Alessandro
• SALAS Raquel GARCIA
• WRIGHT Paul Anthony

Classifications

• F01N3/2066

  Selective catalytic reduction [SCR] · CPC title

• B01D53/9436

  Ammonia · CPC title

• B01D2255/30

  Silica · CPC title

• B01J37/0018

  Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat) · CPC title

• C01B37/06

  Aluminophosphates containing other elements, e.g. metals, boron · CPC title