SUPPORT FOR SILVER CATALYST IN ETHYLENE OXIDE PRODUCTION, METHODS FOR PREPARING THE SAME, SILVER CATALYST PREPARED THEREFROM, AND USE THEREOF

• US 20120065055A1
• Filed: 09/13/2011
• Published: 03/15/2012
• Est. Priority Date: 09/13/2010
• Status: Active Grant

• Current Assignee: Beijing Research Institute of Chemical Industry, China Petroleum & Chemical Corporation (Central People's Government of The People's Republic of China)
• Original Assignee: Beijing Research Institute of Chemical Industry, China Petroleum & Chemical Corporation (Central People's Government of The People's Republic of China)
• Inventors: LIN, Wei, JIANG, Jun, CHEN, Jianshe, LI, Jinbing, LI, Shuyun, ZHANG, Zhixiang, XUE, Qian
• Granted Patent: US 9,006,127 B2
• Time in Patent Office: Days
• US Class Current: 502/216
• CPC Class Codes: B01J 21/04 Alumina
• CPC Class Codes: B01J 23/50 Silver
• CPC Class Codes: B01J 23/58 with alkali- or alkaline earth metals
• CPC Class Codes: B01J 27/12 Fluorides
• CPC Class Codes: B01J 27/13 Platinum group metals
• CPC Class Codes: B01J 27/138 with alkaline earth metals, magnesium, beryllium, zinc, cadmium or mercury
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 35/40 characterised by dimensions, e.g. grain size in a colloidal state B01J35/23; crystallite size B01J35/77
• CPC Class Codes: B01J 35/50 characterised by their shape or configuration
• CPC Class Codes: B01J 35/56 Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• 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 37/0009 Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
• CPC Class Codes: B01J 37/0201 Impregnation
• CPC Class Codes: B01J 37/0213 Preparation of the impregnating solution
• CPC Class Codes: B01J 37/08 Heat treatment B01J37/0009, B01J37/0018 take precedence

Abstract

The present invention relates to a support for silver catalyst used in the ethylene oxide production, a preparation method for the same, a silver catalyst prepared from the same, and its use in the ethylene oxide production. The silver catalyst produced from the silver catalyst support has an improved activity, stability and/or selectivity in the production of ethylene oxide by epoxidation of ethylene.

Claims

1-13. -13. (canceled)

14. An alumina support comprising:

a backbone having a main crystal phase that comprises alpha-alumina;

wherein said alumina support comprises;

a specific surface area of 3.0 m²/g or smaller;

a pore volume between 0.3 ml/g and 0.8 ml/g;

an alkaline-earth metal content between 0.05 wt % and 1.8 wt %, as determined based on the weight of the alkaline-earth metal and the weight of the support; and

a fluorine atom percent content on the surface of the alumina support, of 0.3-8.0% by atom.

20. A process for preparing an alumina support, which process comprises:

(a) mixing an alumina starting material, an alkaline-earth metal salt, a carbonaceous burnout material, a fluoride, a binder and water to form a mixture, wherein based on the total weight of the alumina starting material, the alkaline-earth metal salt is present in an amount of 0.05-2.0% by weight calculated on alkaline-earth metal, the carbonaceous burnout material is present in an amount of 0-30% by weight, the fluoride is present in an amount of 0-3% by weight, the binder and water are present in a total amount of 15-30% by weight;

(b) extruding the mixture obtained in step (a) into shape to give a shaped body of the alumina support;

(c) drying the shaped body of step (b) at a temperature between 60°

C. and 200°

C.;

(d) calcining the shaped body of step (c) at a temperature between 1,200°

C. and 1,600°

C. for alpha-alumina conversion, thereby rendering a semi-finished support;

(e) treating the semi-finished support of step (d) with an acidic fluorine-containing solution having a fluorine content of 0.1-4.0 wt %, preferably 0.2-3.0 wt %, more preferably 0.3-2.0 wt % calculated on fluorine atom and a pH of less than 5; and

(f) further heat-treating the support treated in step (e).

21. The process according to claim 20, wherein step (f) is conducted at a temperature between 200°

C. and 950°

C.

22. The process according to claim 20, wherein:

the carbonaceous burnout material comprises petroleum coke, carbon powder, graphite, polyethylene, polypropylene, rosin, vaseline, or a mixture thereof;

the alkaline-earth metal salt comprises a salt of barium, magnesium, calcium and/or strontium, preferably chloride, sulfate, nitrate, phosphate or oxalate thereof, or a mixture thereof;

the fluoride comprises hydrogen fluoride, ammonium fluoride, aluminum fluoride, magnesium fluoride, cryolite, or a mixture thereof; and

the binder is an acid.

23. The process according to claim 20, wherein the alumina starting material comprises trihydrate alpha-alumina and pseudo-boehmite, wherein the weight ratio of trihydrate alpha-alumina to pseudo-boehmite is between 1:

1 and 6;

1, wherein a portion or all of the trihydrate alpha-alumina is optionally replaced by an alumina powder that is pre-calcined into alpha-alumina or a transition alumina;

wherein a portion or all of the pseudo-boehmite is optionally replaced by alumina sol; and

wherein the ratio of the total weight of trihydrate alpha-alumina and its substitute, if present, to the total weight of pseudo-boehmite and its substitute, if present, is between 1;

1-6;

1.

24. The process according to claim 20, wherein the support is washed with distilled water or deionized water for 1-5 times after step (e) and prior to step (f).

25. The process according to claim 20, wherein the heat-treatment in step (f) is conducted at a temperature between 200°

C. and 900°

C. for 5-600 minutes.

26. The process according to claim 25, wherein the heat-treatment in step (f) is conducted in a flowing atmosphere having a moisture content of less than 1 wt %, air, or an inert atmosphere.

27. The process according to claim 20, wherein one or more organic fluorine-containing carboxylic acids containing 2-6 fluorine atoms such as trifluoroacetic acid and pentafluoropropionic acid, and/or a combination of a soluble fluoride such as ammonium fluoride and a decomposable or volatilizable acid such as oxalic acid is/are used as a solute of the acidic fluorine-containing solution.