Porous bodies with enhanced pore architecture

Patent metadata

Field	Value
Publication number	US-9776169-B2
Application number	US-201615171278-A
Country	US
Kind code	B2
Filing date	Jun 2, 2016
Priority date	Jun 2, 2015
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A porous body is provided with enhanced fluid transport properties that is capable of performing or facilitating separations, or performing reactions and/or providing areas for such separations or reactions to take place. The porous body includes at least 80 percent alpha alumina and has a pore volume from 0.3 mL/g to 1.2 mL/g and a surface area from 0.3 m 2 /g to 3.0 m 2 /g. The porous body further includes a pore architecture that provides at least one of a tortuosity of 7.0 or less, a constriction of 4.0 or less and a permeability of 30 mdarcys or greater. The porous body can be used in a wide variety of applications such as, for example, as a filter, as a membrane or as a catalyst carrier.

First claim

What is claimed is:

1. A porous body comprising:
at least 80 percent alpha alumina and having a pore volume from 0.3 mL/g to 1.2 mL/g, a surface area from 0.3 m 2 /g to 3.0 m 2 /g, and a pore architecture that provides at least one of a tortuosity of 7 or less, a constriction of 4 or less and a permeability of 30 mdarcys or greater.

2. The porous body of claim 1 , wherein at least 90 percent of said pore volume is attributed to pores having a pore size of 20 microns or less.

3. The porous body of claim 1 , wherein at least 85 percent of said pore volume is attributed to pores having a size from 1 micron to 6 microns.

4. The porous body of claim 1 , wherein less than 15 percent of said pore volume is attributed to pores having a size of less than 1 micron.

5. The porous body of claim 1 , wherein at least 80 percent of said pore volume is attributed to pores having a size from 1 micron to 10 microns.

6. The porous body of claim 1 , further comprising a silica content, as measured as SiO 2 , of less than 0.2 weight percent, and a sodium content, as measured as Na 2 O, of less than 0.2 weight percent.

7. The porous body of claim 1 , further comprising an acid leachable sodium content of 40 ppm or less.

8. The porous body of claim 1 , wherein said pore architecture provides said tortuosity and said constriction.

9. A silver-based epoxidation catalyst comprising:
a carrier comprising at least 80 percent alpha alumina and having a pore volume from 0.3 mL/g to 1.2 mL/g, a surface area from 0.3 m 2 /g to 3.0 m 2 /g, and a pore architecture that provides at least one of a tortuosity of 7 or less, a constriction of 4 or less and a permeability of 30 mdarcys or greater;
a catalytic amount of silver disposed on and/or in said carrier; and
a promoting amount of one or more promoters disposed on said carrier.

10. The silver-based epoxidation catalyst of claim 9 , wherein said one or more promoters comprise Group 1 alkali metal promoters, one or more transition metals, one or more Group 2 alkaline earth metals or any combination thereof.

11. The silver-based epoxidation catalyst of claim 10 , wherein said one or more transition metals are selected from the group consisting of Groups 4-10 of the Periodic Table of the Elements.

12. The silver-based epoxidation catalyst of claim 11 , wherein said one or more transition metals are selected from the group consisting of molybdenum, rhenium, tungsten, chromium, titanium, hafnium, zirconium, vanadium, thorium, tantalum, and niobium.

13. The silver-based epoxidation catalyst of claim 10 , wherein said one or more transition metals comprise rhenium, molybdenum, tungsten, or any combination thereof.

14. The silver-based epoxidation catalyst of claim 10 , wherein said Group 1 alkali metal promoters are selected from the group consisting of cesium, lithium, sodium, potassium, and rubidium.

15. The silver-based epoxidation catalyst of claim 14 , wherein said Group 1 alkali metal promoters comprise lithium and cesium.

16. The silver-based epoxidation catalyst of claim 9 , wherein said one or more promoters comprises a promoting combination of rhenium, cesium and lithium.

17. The silver-based epoxidation catalyst of claim 9 , wherein said catalytic amount of silver is from 10 to 50% by weight.

18. The silver-based epoxidation catalyst of claim 9 , wherein at least 90 percent of said pore volume is attributed to a pore size of 20 microns or less.

19. The silver-based epoxidation catalyst of claim 9 , wherein at least 85 percent of said pore volume is attributed to pores having a size from 1 micron to 6 microns.

20. The silver-based epoxidation catalyst of claim 9 , wherein less than 15 percent of said pore volume is attributed to pores having a size of less than 1 micron.

21. The silver-based epoxidation catalyst of claim 9 , wherein at least 80 percent of said pore volume is attributed to pores having a size from 1 micron to 10 microns.

22. The silver-based epoxidation catalyst of claim 9 , wherein said carrier has a silica content, as measured as SiO 2 , of less than 0.2 weight percent, and a sodium content, as measured as Na 2 O, of less than 0.2 weight percent.

23. The silver-based epoxidation catalyst of claim 9 , wherein said carrier has a water washing acid leachable sodium content of 40 ppm or less.

24. The silver-based epoxidation catalyst of claim 9 , wherein said carrier has alumina crystallites having a platelet morphology in a content of less than 20 percent by volume.

25. The silver-based epoxidation catalyst of claim 9 , wherein said pore architecture provides said tortuosity and said constriction.

26. A catalyst composition comprising:
a carrier comprising at least 80 percent alpha alumina and having a pore volume from 0.3 mL/g to 1.2 mL/g, a surface area from 0.3 m 2 /g to 3.0 m 2 /g, and a pore architecture that provides at least one of a tortuosity of 7 or less, a constriction of 4 or less and a permeability of 30 mdarcys or greater; and
a catalytic amount of at least one catalytically active material disposed on and/or in said carrier.

27. The catalyst composition of claim 26 , wherein said carrier has a silica content, as measured as SiO 2 , of less than 0.2 weight percent, and a sodium content, as measured as Na 2 O, of less than 0.2 weight percent.

Assignees

• Scient Design Co

Inventors

• Suchanek Wojciech L

Classifications

• C04B41/4535

  applied as a solution, emulsion, dispersion or suspension · CPC title

• C04B38/08

  by adding porous substances · CPC title

• B01J23/50

  Silver · CPC title

• C04B41/88

  Metals · CPC title

• C04B2111/0081

  as catalysts or catalyst carriers · CPC title