Catalyst for production of ethylene oxide and method for production of ethylene oxide

• US 7,560,577 B2
• Filed: 09/27/2007
• Issued: 07/14/2009
• Est. Priority Date: 09/29/2006
• Status: Expired due to Fees

• Current Assignee: Nippon Shokubai Company Limited
• Original Assignee: Nippon Shokubai Company Limited
• Inventors: Mikawa, Masatsugu, Yunoki, Hiromi, Hirota, Hiroyuki
• Primary Examiner(s): Dentz; Bernard
• Assistant Examiner(s): Gallis; David E
• Application Number:
  US11/905,039
• Publication Number:
  US 20080091038A1
• Time in Patent Office: 656 Days
• Field of Search: 549/534, 549/536, 549/537, 502/415, 502/355, 502/347, 502/117, 502/263, 502/348
• US Class Current: 549/534
• CPC Class Codes: B01J 23/50 Silver
• CPC Class Codes: B01J 23/54 combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
• CPC Class Codes: B01J 35/612 less than 10 m2/g
• CPC Class Codes: B01J 35/633 less than 0.5 ml/g
• CPC Class Codes: B01J 35/635 0.5-1.0 ml/g
• CPC Class Codes: B01J 35/651 50-500 nm
• CPC Class Codes: B01J 35/653 500-1000 nm
• CPC Class Codes: B01J 35/657 larger than 1000 nm
• CPC Class Codes: B01J 37/0205 in several steps
• CPC Class Codes: B01J 37/0207 Pretreatment of the support
• CPC Class Codes: C07D 301/04 with air or molecular oxygen
• CPC Class Codes: C07D 301/10 with catalysts containing silver or gold
• CPC Class Codes: Y02P 20/52 using catalysts, e.g. selective catalysts

Abstract

A catalyst that enables to produce ethylene oxide in a high selectivity and a method for the production of ethylene oxide using the catalyst are provided. In the catalyst for the production of ethylene oxide, wherein the catalyst component is supported by a carrier, a carrier containing α-alumina as the main component which has at least two peaks in the range of pore diameter of 0.01-100 μm and at least one peak of the above peaks is present in the range of pore diameter of 0.01-1.0 μm in the pore distribution measured by mercury porosimetry is adopted as said carrier.

Claims

1. A catalyst for the production of ethylene oxide, comprising:

a carrier containing α

-alumina as the main component which has at least two log differential pore volume distribution peaks in a pore diameter range of 0.01-100 μ

m and at least one peak of the above peaks is present in a pore diameter range of 0.01-1.0 μ

m in the pore distribution measured by mercury porosimetry, wherein each peak is a maximum value of the log differential pore volume distribution of 0.2 cm³/g or larger, and a catalyst component comprising silver is supported on the carrier.

2. The catalyst for the production of ethylene oxide according to claim 1, wherein the specific surface area of said carrier is 0.03-10 m²/g.

3. The catalyst for the production of ethylene oxide according to claim 1, wherein the pore volume of said carrier is 0.2-0.6 cm³/g.

4. The catalyst for the production of ethylene oxide according to claim 1, wherein the ratio of the pore volume of the pore having a pore diameter of 0.1-0.5 μ

m relative to the total pore volume of said carrier is 5-50 vol %.

5. The catalyst for the production of ethylene oxide according to claim 1, wherein the median pore diameter of said carrier is 0.1-10 μ

m.

6. The catalyst for the production of ethylene oxide according to claim 1, wherein the water absorption of said carrier is 10-70%.

7. The catalyst for the production of ethylene oxide according to claim 1, wherein the primary particle diameter of the α

-alumina, the raw material of said carrier is 0.01-100 μ

m, and the secondary particle diameter is 0.1-1,000 μ

m.

8. The catalyst for the production of ethylene oxide according to claim 1, wherein the mean diameter of said carrier is 3-20 mm.

9. The catalyst for the production of ethylene oxide according to claim 1, wherein the content of the α

-alumina in said carrier is 90 mass % or more relative to the total mass of the carrier.

10. The catalyst for the production of ethylene oxide according to claim 1, wherein the content of an oxide of an alkali metal or an alkaline-earth metal in said carrier is 0-5 mass % in terms of the oxide relative to the total mass of the carrier.

11. The catalyst for the production of ethylene oxide according to claim 1, wherein the content of an oxide of a transition metal in said carrier is 0-5 mass % in terms of the oxide relative to the total mass of the carrier.

12. The catalyst for the production of ethylene oxide according to claim 1, wherein the content of silica in said carrier is 0.01-10.0 mass % relative to the total mass of the carrier.

13. The catalyst for the production of ethylene oxide according to claim 1, wherein said catalyst component includes cesium as a reaction promoter.

14. The catalyst for the production of ethylene oxide according to claim 1, wherein an amount of silver to be supported as said catalyst component is 1-30 mass % relative to the mass of the catalyst for the production of ethylene oxide.

15. The catalyst for the production of ethylene oxide according to claim 1, wherein an amount of said reaction promoter to be supported is 0.001-2 mass % relative to the mass of the catalyst for the production of ethylene oxide.

16. A method for the production of ethylene oxide comprising conducting catalytic vapor phase oxidation of ethylene with a molecular oxygen-containing gas in a gas phase with a gas containing molecular oxygen in the presence of the catalyst according to claim 1.