Molecular sieves and related methods and structure directing agents

Patent metadata

Field	Value
Publication number	US-9957166-B2
Application number	US-201615044041-A
Country	US
Kind code	B2
Filing date	Feb 15, 2016
Priority date	Apr 9, 2009
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

Method for preparing molecular sieves and molecular sieves obtained thereby are described. The method includes preparing a reaction mixture, comprising a structure directing agent, at least one source of at least one oxide of a tetravalent element, optionally, one or more sources of one or more oxides selected from the group consisting of oxides of trivalent elements, pentavalent elements, and mixtures thereof, optionally, at least one source of an element selected from Groups 1 and 2 of the Periodic Table; and optionally, hydroxide ions or fluoride ions, and maintaining the reaction mixture under conditions sufficient to form crystals of the molecular sieve. In the method, various imidazolium cations are used as the structure directing element.

First claim

The invention claimed is:

1. A method for preparing an as-synthesized molecular sieve SSZ-70, the method comprising:
preparing a reaction mixture comprising:
a structure directing agent comprising an imidazolium cation of formula 1, 2, 3, 4, 5, or 12:

at least one source of at least one oxide of a tetravalent element;
optionally, one or more sources of one or more oxides selected from the group consisting of oxides of trivalent elements, pentavalent elements, and mixtures thereof;
optionally, at least one source of an element selected from Groups 1 and 2 of the Periodic Table; and
optionally, hydroxide ions or fluoride ions; and

maintaining the reaction mixture for a time and under conditions suitable to form crystals of the molecular sieve SSZ-70,
to thereby obtain the as-synthesized molecular sieve SSZ-70.

2. The method of claim 1 , wherein an imidazolium cation is associated with an anion selected from the group consisting of hydroxide, fluoride, chloride, bromide, iodide, acetate, sulfate, tetrafluoroborate and carboxylate.

3. The method of claim 1 , wherein the tetravalent element is selected from the group consisting of silicon, germanium and titanium.

4. The method of claim 1 , wherein the tetravalent element is silicon.

5. The method of claim 1 , wherein the source of the tetravalent element is selected from the group consisting of oxides, hydroxides, acetates, oxalates, ammonium salts and sulfates of the tetravalent element.

6. The method of claim 1 , wherein the source of an element selected from Groups 1 and 2 of the Periodic Table is selected from the group consisting of an alkali metal hydroxide and an alkaline earth metal hydroxide.

7. The method of claim 6 , wherein the alkali metal hydroxide is selected from the group consisting of sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide and rubidium hydroxide.

8. The method of claim 6 , wherein the alkaline earth metal hydroxide is selected from the group consisting of calcium hydroxide and magnesium hydroxide.

9. The method of claim 1 , wherein the trivalent element is selected from the group consisting of boron, aluminum, gallium and iron.

10. The method of claim 1 , wherein the trivalent element is boron.

11. The method of claim 1 , wherein the reaction mixture comprises hydroxide ions, SiO 2 and B 2 O 3 , and wherein the mole ratio between SiO 2 and B 2 O 3 is about 20-200 to 1.

12. The method of claim 1 , wherein the reaction mixture comprises hydroxide ions, SiO 2 and Al 2 O 3 , and wherein the mole ratio between SiO 2 and Al 2 O 3 is about 30-45 to 1.

13. The method of claim 1 , wherein the reaction mixture comprises hydroxide ions or fluoride ions, SiO 2 and GeO 2 , and wherein the mole ratio between SiO 2 and GeO 2 is about 2-50 to 1.

14. The method of claim 1 , wherein the reaction mixture comprises fluoride ions SiO 2 and Al 2 O 3 , and wherein the mole ratio between SiO 2 and Al 2 O 3 is about 30-500 to 1.

15. The method of claim 1 , wherein the conditions suitable to form crystals of the molecular sieve comprise maintaining the reaction mixture at a temperature between about 125° C. and about 200° C. until the molecular sieve is formed.

16. The method of claim 15 , further including maintaining the reaction mixture under pressure in the range between about 0.34 MPa and about 1.38 MPA.

17. The method of claim 1 , further including calcinating the as-synthesized molecular sieve by thermal treatment in an oxidative atmosphere.

18. The method of claim 17 , wherein the process of calcination is conducted in an atmosphere selected from the group consisting of steam, air and an inert gas at a temperature between about 200° C. and about 800° C. for a period of time that is at least 1 hour.

19. The method of claim 1 , wherein the reaction mixture comprises hydroxide ions, SiO 2 and B 2 O 3 , and wherein the mole ratio between SiO 2 and B 2 O 3 is about 200 to 1.

20. The method of claim 1 , wherein the reaction mixture comprises hydroxide ions, SiO 2 and Al 2 O 3 , and wherein the mole ratio between SiO 2 and Al 2 O 3 is about 45 to 1.

21. An as-synthesized molecular sieve SSZ-70 comprising TO 2 , X 2 O a , a metal, a fluoride and a structure directing agent,
wherein
the mole ratio between TO 2 and X 2 O a is at least about 2;
the mole ratio between the metal and TO 2 is between about 0 and about 0.03;
the mole ratio between the structure directing agent and TO 2 is between about 0.02 and about 0.06, and
the mole ratio between the fluoride and TO 2 is between about 0 and about 0.08;
and wherein:
T is selected from the elements from Groups 4-14 of the Periodic Table or a combination thereof;
X is selected from the elements from Groups 3-13 of the Periodic Table, or a combination thereof;
a=3 when X is trivalent; a=5 when X is pentavalent;
the metal is selected from the group consisting of alkali metals and alkaline earth metals, or a combination thereof; and
the structure directing agent is an imidazolium cation
selected from the group consisting of:

22. The molecular sieve of claim 21 , wherein T is selected from the group consisting of silicon, germanium and titanium.

23. The molecular sieve of claim 21 , wherein X is selected from the group consisting of gallium, aluminum, iron and boron.

Assignees

• California Inst Of Techn

Inventors

• Archer Raymond
• Davis Mark E

Classifications

• C01B37/005

  Silicates, i.e. so-called metallosilicalites or metallozeosilites · CPC title

• B01J29/047

  Germanosilicates; Aluminogermanosilicates (B01J29/005 takes precedence) · CPC title

• B01J29/7007

  Zeolite Beta · CPC title

• C01B39/08

  the aluminium atoms being wholly replaced · CPC title

• C01B39/48 Primary

  using at least one organic template directing agent · CPC title