Process for manufacturing MCM-22 family molecular sieves

Abstract

A method of manufacturing a molecular sieve of the MCM-22 family, said method comprising the steps of (a) providing a mixture comprising at least one source of ions of tetravalent element, at least one source of alkali metal hydroxide, at least one directing-agent (R), water, and optionally at least one source of ions of trivalent element, said mixture having the following mole composition: Y:X2=10 to infinityH2O:Y=1 to 20OH−:Y=0.001 to 2M+:Y=0.001 to 2R:Y=0.001 to 0.34 wherein Y is a tetravalent element, X is a trivalent element, M is an alkali metal; (b) treating said mixture at crystallization conditions for less than 72 hr to form a treated mixture having said molecular sieve, wherein said crystallization conditions comprise a temperature in the range of from about 160° C. to about 250° C.; and (c) recovering said molecular sieve.

Description

DESCRIPTION OF THE FIGURES

FIG. 1 is X-ray diffraction patterns of the crystalline material product of Comparative Example.

FIG. 2 is X-ray diffraction patterns of the crystalline material product of Example 1.

FIG. 3 is X-ray diffraction patterns of the crystalline material product of Example 2.

FIG. 4 is X-ray diffraction patterns of the crystalline material products of Example 3 at 24 hours.

FIG. 5 is the SEM image of the crystalline material product of Comparative Example.

FIG. 6 is the SEM image of the crystalline material product of Example 1.

Claims

1. A method of manufacturing a molecular sieve of the MCM-22 family, said method comprising the steps of: (a) providing a mixture comprising at least one source of ions of tetravalent element, at least one source of alkali metal hydroxide, at least one directing-agent (R), water, and optionally at least one source of ions of trivalent element, said mixture having the following mole composition: Y:X2=10 to infinityH2O:Y=1 to 20OH−:Y=0.001 to 2M+:Y=0.001 to 2R:Y=0.001 to 0.34wherein Y is a tetravalent element, X is a trivalent element, M is an alkali metal;(b) treating said mixture at crystallization conditions for less than 72 hr to form a treated mixture comprising said molecular sieve, wherein said crystallization conditions comprise a temperature in the range of from about 160° C. to about 250° C.; and(c) recovering said molecular sieve.

2. The method recited in claim 1, wherein said molecular sieve formed in step (b) is substantially free of non-MCM-22 family material(s).

3. The method recited in claim 1, wherein said molecular sieve is a crystalline molecular sieve of the MCM-22 family.

4. The method recited in claim 1, wherein said crystallization conditions comprise a weight hourly throughput of at least 0.001 hr−1.

5. The method recited in claim 1 wherein said crystallization conditions comprise a weight hourly throughput of at least 0.002 hr−1.

6. The method recited in claim 1, wherein said crystallization conditions comprise a weight hourly throughput of at least 0.004 hr−1.

7. The method recited in claim 1, wherein step (b) is performed in the presence of seed crystals.

8. The method recited in claim 1, wherein said mixture comprises from about 0.0001 to 20 wt. % of at least one seed source (Seed) based on the total weight of said mixture.

9. The method recited in claim 1, wherein said crystallization conditions comprise a temperature in the range of from about 165° C. to about 210° C., and crystallization time less than 48 hr.

10. The method recited in claim 1, wherein said crystallization conditions comprise a temperature in the range of from about 170° C. to about 210° C., and crystallization time less than 24 hr.

11. The method of claim 1, wherein said step (b) further comprises an agitating step.

12. The method of claim 11, wherein said agitating step comprises at least one of a tumbling step, a stirring step, or any combination thereof.

13. The method of claim 1, further comprising a step of recovering at least a portion of said directing-agent.

14. The method of claim 13, wherein said recovering step comprising the steps of: (a) flashing at least a portion of said directing-agent in vapor phase from said treated mixture; and(b) condensing said vapor phase directing-agent.

15. The method of claim 14, further comprising a step of reusing at least a portion of said condensed directing-agent to as a component of a synthesis mixture for manufacture of a molecular sieve.

16. The method recited in claim 1, wherein said crystalline molecular sieve comprises at least one of MCM-22, MCM-49, MCM-56, a mix-phase of MCM-22 and MCM-49, a mix-phase of MCM-22 and MCM-56, a mix-phase of MCM-56 and MCM-49, and a mix-phase of MCM-22, MCM-49, and MCM-56.

17. The method recited in claim 1, wherein said crystalline molecular sieve has a composition comprising the mole relationship on an anhydrous basis as: X2O3:(n)YO2

18. The method recited in claim 1, wherein the solids content of the synthesis mixture (being the percentage by weight of tetravalent element oxide and, when present, trivalent element oxide in the synthesis mixture, based on the total weight of the synthesis mixture) is at least 12 wt. %.

19. The method of claim 14 wherein the solids content is at least 20 wt. %.

20. The method of claim 14 wherein the solids content is at least 30 wt. %.

21. The method recited in claim 1, wherein said tetravalent element is silicon and said source of ions of tetravalent element is silica.

22. The method recited in claim 1, wherein said optionally trivalent element is aluminum and said optionally source of ions of trivalent element is alumina.

23. A method of crystallizing a molecular sieve of the MCM-22 family, said method comprising the steps of: (a) providing a mixture comprising at least one source of ions of tetravalent element, at least one source of alkali metal hydroxide, at least one directing-agent (R), water, and optionally at least one source of ions of trivalent element, said mixture having the following mole composition: Y:X2=10 to infinityH2O:Y=1 to 20OH−:Y=0.001 to 2M+:Y=0.001 to 2R:Y=0.001 to 0.34wherein Y is a tetravalent element X is a trivalent element, M is an alkali metal; and(b) treating said mixture to form said molecular sieve at crystallization conditions for less than 72 hr, wherein said crystallization conditions comprise a temperature in the range of from about 160° C. to about 250° C. and a weight hourly throughput of at least 0.001 hr−1.

24. The method recited in claim 20, having a weight hourly throughput of at least 0.002 hr−1.

25. The method recited in claim 20, having a weight hourly throughput of at least 0.004 hr−1.

26. The method recited in claim 20, wherein said mixture further comprising an effective amount of at least one seed source (Seed), said effective amount ranges from about 0.01 to 20 wt. % of the total weight of said mixture.

27. The method recited in claim 20, wherein said crystallization conditions comprise a temperature in the range of from about 165° C. to about 210° C., and crystallization time less than 48 hr.

28. The method recited in claim 20, wherein said crystallization conditions comprise a temperature in the range of from about 170° C. to about 210° C. and crystallization time less than 24 hr.

29. The method of claim 20, wherein said step (b) further comprises an agitating step.

30. The method recited in claim 20, wherein said crystalline molecular sieve comprises at least one of MCM-22, MCM-49, MCM-56, a mix-phase of MCM-22 and MCM-49, a mix-phase of MCM-22 and MCM-56, a mix-phase of MCM-56 and MCM-49, and a mix-phase of MCM-22, MCM-49, and MCM-56.

31. The method recited in claim 20, wherein the solids content of the synthesis mixture (being the percentage by weight of tetravalent element oxide and, when present, trivalent element oxide in the synthesis mixture, based on the total weight of the synthesis mixture) is at least 12 wt. %.

32. The method of claim 28 wherein the solids content is at least 20 wt. %.

33. The method of claim 28 wherein the solids content is at least 30 wt. %.

34. The method recited in claim 20, wherein said tetravalent element is silicon and said source of ions of tetravalent element is silica.

35. The method recited in claim 20, wherein said optionally trivalent element is aluminum and said optionally source of ions of trivalent element is alumina.

36. A molecular sieve manufactured by a method comprising the step of: (a) providing a mixture comprising at least one source of ions of tetravalent element, at least one source of alkali metal hydroxide, at least one directing-agent (R), water, and optionally at least one source of ions of trivalent element, said mixture having the following mole composition: Y:X2=10 to infinityH2O:Y=1 to 20OH−:Y=0.001 to 2M+:Y=0.001 to 2R:Y=0.001 to 0.34wherein Y is a tetravalent element, X is a trivalent element, M is an alkali metal;(b) treating said mixture to form said molecular sieve at crystallization conditions, wherein said crystallization conditions comprise a temperature in the range of from about 165° C. to about 250° C., and crystallization time less than 72 hr; and(c) recovering said molecular sieve,wherein said molecular sieve is characterized by an X-ray diffraction pattern of as-synthesized said molecular sieve including d-spacing maxima at 12.4±0.25, 3.57±0.07 and 3.42±0.07 Angstroms and at least one peak between 26.6° and 29° (2θ).

37. The molecular sieve recited in claim 33, wherein said X-ray diffraction pattern has a peak between 26.6° and 29° (2θ) with a two theta (2θ) value of about 26.9°.

38. The molecular sieve recited in claim 33, wherein said molecular sieve has a platelet morphology having a crystal thickness at least 300 Å measured by SEM.

39. A hydrocarbon conversion process, said process comprising the steps of: (a) contacting a hydrocarbon feedstock with a molecular sieve of the MCM-22 family recited in claim 36 under conversion conditions to form a product; and(b) withdrawing said product.

40. The process of claim 36, wherein said hydrocarbon feedstock comprises at least one of C1-C20 hydrocarbons and C1-C20 oxygenates.

41. The process of claim 36, wherein said conversion conditions comprise a temperature ranging from about 100° C. to 950° C., a pressure ranging from about 101 kPa-a to 50000 kPa-a, and a WHSV ranging from about 0.001 to 1000 hr−1.

42. The process of claim 36, wherein said hydrocarbon conversion is alkylation of benzene with ethylene to from ethylbenzene.

43. The process of claim 36, wherein said hydrocarbon conversion is alkylation of benzene with propylene to from cumene.