Porous inorganic body

Patent metadata

Field	Value
Publication number	US-9468906-B2
Application number	US-201313780310-A
Country	US
Kind code	B2
Filing date	Feb 28, 2013
Priority date	Mar 2, 2012
Publication date	Oct 18, 2016
Grant date	Oct 18, 2016

Abstract

The present invention relates to a porous inorganic body comprising pores A having a pore size S A in the range of from 0.005 to 20 micrometer and a total pore volume V A , and comprising pores B having a pore size S B in the range of from more than 20 to 1000 micrometer and a total pore volume V B , wherein the total pore volume of the pores having a pore size in the range of from 0.005 to 1000 micrometer is V C and wherein the ratio R A =V A /V C is in the range of from 0.3 to 0.7 as determined via mercury intrusion porosimetry.

First claim

The invention claimed is:

1. A porous inorganic body comprising pores A having a pore size S A in the range of from 0.005 to 20 micrometer and a total pore volume V A , and pores B having a pore size S B in the range of from more than 20 to 1000 micrometer and a total pore volume V B , wherein the total pore volume of the pores having a pore size in the range of from 0.005 to 1000 micrometer is V C , and wherein a ratio R A =V A /V C is in the range of from 0.3 to 0.7 as determined via mercury intrusion porosimetry according to DIN 66133.

2. The inorganic body of claim 1 , wherein R A is in the range of from 0.35 to 0.65.

3. The inorganic body of claim 1 , wherein S A is in the range of from 0.1 to 20 micrometer and S B is in the range of from 100 to 1000 micrometer.

4. The inorganic body of claim 1 , wherein S A is in the range of from 0.4 to 20 micrometer.

5. The inorganic body of claim 1 , wherein the differential intrusion determined via mercury intrusion porosimetry according to DIN 66133 as a function of the pore size contains at least one peak in the pore size range of from 0.005 to 20 micrometer and at least one peak in the pore size range of from 20 to 1000 micrometer.

6. The inorganic body of claim 1 , having a specific surface area (BET) as determined according to DIN ISO 9277 in the range of from 0.5 to 1.5 m 2 /g.

7. The inorganic body of claim 1 , having a specific surface area (BET) as determined according to DIN ISO 9277 in the range of from 0.8 to 1.2 m 2 /g.

8. The inorganic body of claim 1 , having a water absorption in the range of from 0.4 to 1.5 ml/g.

9. The inorganic body of claim 1 , at least 95 weight-% thereof being comprised of alumina.

10. The inorganic body of claim 1 , at least 99 weight-% thereof being comprised of alpha alumina.

11. The inorganic body of claim 1 , comprising at least one element selected from the group consisting of alkali metals, alkaline earth metals, silicon, and iron.

12. The inorganic body of claim 1 , comprising of from 200 to 750 weight-ppm of sodium, up to 600 weight-ppm, of silicon, and up to 100 weight-ppm of iron, based on the total weight of the inorganic body, calculated as element and as determined via elemental analysis.

13. The inorganic body of claim 1 , having the geometry of a cylinder, having a length in the range of from 3 to 20 mm, an outer diameter in the range of from 2 to 20 mm, and a ratio of outer diameter (in mm) relative to wall thickness (in mm) in the range of from 1 to 15.

14. The inorganic body of claim 1 , having the geometry of a cylinder, having a length in the range of from 5 to 10 mm, an outer diameter in the range of from 5 to 10 mm, and a ratio of outer diameter (in mm) relative to wall thickness (in mm) in the range of from 2.5 to 4.5.

15. A catalyst carrier or a catalyst which comprises the inorganic body of claim 1 .

16. A process for the preparation of a porous inorganic body of claim 1 , said process comprising
a) supplying a sinterable inorganic powder, preferably an alumina powder, more preferably an alpha alumina powder, at a first zone of a temperature-controllable zoned extruder comprising a die head and at least 3 zones;
supplying an aqueous solution comprising a binder or an aqueous suspension comprising a binder at a second zone of the zoned extruder downstream of the first zone;
c) mixing the sinterable inorganic powder and the aqueous solution or suspension in the extruder to yield a mixture;
d) heating the mixture in the zoned extruder up to a temperature of at most 200° C. at an essentially constant volume, thus increasing the pressure and at least partially vaporizing the water comprised in the mixture to yield a pressurized mixture;
e) expanding the pressurized mixture into a volume which is at a pressure lower than that of the pressurized mixture to yield a non-flowable intermediate body after extrusion via the die head;
f) optionally, subjecting the intermediate body to a temperature of from 100° C. to 120° C. to remove remaining water from the intermediate body to yield a green body;
g) calcining the green body or the intermediate body at a temperature of from 300° C. to 1100° C.;
h) optionally, sintering the calcined green body at a temperature higher than the calcination temperature up to at most 2000° C. to yield the porous inorganic body;
wherein said process is preferably a continuous process.

17. The process of claim 16 , wherein the temperature of the mixtures in the extruder zones prior to step d) is below 100° C.

18. The process of claim 16 , wherein the temperature-controllable zoned extruder is configured as a double-screw extruder.

19. The process of claim 16 , wherein the dead volume of the die head of the temperature-controllable zoned extruder is at most 25 ml.

20. The process of claim 16 , wherein the die head of the temperature-controllable zoned extruder is equipped with a nozzle having an output side and wherein the nozzle has a wall width at the output side of at most 1 mm.

21. The process of claim 16 , wherein prior to step d), and prior to step c), at least one plasticizing agent is added.

22. The process of claim 16 , wherein prior to step d), at least one pore-forming agent and/or at least one pore forming agent precursor is added.

23. The process of claim 16 , wherein prior to step d), at least one surface active compound and/or at least one blowing agent precursor is added.

24. The process of claim 16 , wherein the mixture heated in step d) comprises from 50 to 90 weight-% of the inorganic powder, relative to the total weight of the mixture.

25. The process of claim 24 , wherein the mixture heated in step d) comprises, relative to the inorganic powder, from 2 to 20% weight-% of the at least one binder, from 0.5 to 40 weight-% of the at least one plasticizing agent, optionally from 1 to 50 weight-% of the at least one pore-forming agent, optionally from 0.5 to 10 weight-% of the at least one surface active compound, and optionally from 20 to 90 weight-% of the at least one blowing agent precursor.

26. A method for the preparation of ethylene oxide which comprises utilizing the inorganic body according to claim 1 as a catalyst carrier.

27. The inorganic body of claim 1 , wherein R A is in the range of from 0.35 to 0.65; S A is in the range of from 0.4 to 20 micrometer and S B is in the range of from 100 to 1000 micrometer; and the inorganic body comprising a specific surface area (BET) as determined according to DIN ISO 9277 in the range of from 0.8 to 1.2 m 2 /g.

28. The inorganic body of claim 27 , wherein the inorganic body comprises at least 95 weight-% alumina, of which at least 99 weight-% is comprised of alpha alumina.

29. The inorganic body of claim 27 , comprising of from 200 to 750 weight-ppm of sodium, up to 600 weight-ppm, of silicon, and up to 100 weight-ppm of iron, based on the total weight of the inorganic body, calculated as element and as determined via elemental analysis.

30. A catalyst carrier or a catalyst which comprises the inorganic body of claim 27 .

31. A porous inorganic body comprising pores A having a pore size S A in the range of from 0.1 to 20 micrometer and a total pore volume V A , and pores B having a pore size S B in the range of from more than 100 to 1000 micrometer and a total pore volume V B , wherein the total pore

Assignees

• Basf Se

Inventors

• Baltes Christian
• Rosendahl Tobias
• Shishkov Igor
• Mäurer Torsten
• Rohde Wolfgang
• Kraus Martin
• GüNTHERBERG NORBERT
• Queiroz Da Fonseca Isa Alexandra
• Jochum Alfons
• Bouche Siegbert

Classifications

• C07D301/00

  Preparation of oxiranes · CPC title

• B01J37/08

  Heat treatment {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• C04B2111/00129

  Extrudable mixtures · CPC title

• C04B2111/0081

  as catalysts or catalyst carriers · CPC title

• B01J21/16

  Clays or other mineral silicates · CPC title