Copper-containing catalyst for low temperature shift conversion

• US 5,128,307 A
• Filed: 01/30/1991
• Issued: 07/07/1992
• Est. Priority Date: 11/03/1988
• Status: Expired due to Term

• Current Assignee: BASF AG (BASF SE)
• Original Assignee: BASF AG (BASF SE)
• Inventors: Sprague, Michael J., Wanjek, Herbert, Witte, Claus, Irgang, Matthias, Hoelderich, Wolfgang, Mross, Wolf D.
• Primary Examiner(s): MCFARLANE, ANTHONY R
• Application Number:
  US07/649,299
• Time in Patent Office: 524 Days
• Field of Search: 502/341, 502/342, 502/346, 502/344, 502/343, 502/345
• US Class Current: 502/342
• CPC Class Codes: B01J 23/72 Copper
• CPC Class Codes: B01J 23/80 with zinc, cadmium or mercury
• CPC Class Codes: B01J 35/613 10-100 m2/g
• CPC Class Codes: B01J 35/615 100-500 m2/g
• CPC Class Codes: B01J 37/031 Precipitation
• CPC Class Codes: C01B 3/16 using catalysts
• CPC Class Codes: Y02P 20/52 using catalysts, e.g. selective catalysts

Abstract

Copper-containing catalysts for low temperature shift conversion at from 150° to 300° C. and under from 10 to 40 bar, which additionally contain aluminum and zinc, if necessary in the form of the compounds or oxides and are prepared by coprecipitation, the copper-containing catalysts containing potassium and having a BET surface area adapted to the potassium content, and the potassium content being brought to 0.1-3.0% by weight at a BET surface of from 30 to 160 m² /g, are used for the preparation of hydrogen and carbon dioxide from carbon monoxide and water.

Claims

1. A process for the preparation of a copper, aluminum, zinc and potassium containing catalyst for shift conversions which comprises:

(a) coprecipitating in aqueous solution, water-soluble salts of copper, zinc and aluminum at a constant pH value of from 5.5 to 8.0 and at a constant temperature of from 30° and

90°

to form sparingly water-soluble or water-insoluble compounds of copper, zinc and aluminum;

(b) aging the precipitate while maintaining the same pH value as that of the precipitation step during the aging within a tolerance range of ±

0.5 and,

(c) separating and washing the aged precipitate;

(d) adding water-soluble potassium compound, in an amount corresponding to 0.1 to 3.0% by weight of K₂ O based on the mass of the precipitate, and suspending the mixture;

(e) drying and heat-treating the resulting mixture to obtain a catalyst having a BET surface area in the range of from 30 to 160 m² /g.

2. A process as defined in claim 1, wherein the catalyst contains copper, zinc and aluminum in amounts corresponding to from 30 to 50% by weight of CuO, from 5 to 45% by weight of ZnO and from 5 to 50% by weight of Al₂ O₃, based on the calcined catalyst.

3. A process as defined in claim 1, wherein the aging step (b) is carried out by stirring the aqueous suspension of the precipitate.

4. A process as defined in claim 1, wherein the suspended mixture of step (d) has a solids content of 10 30% by weight.

5. A process as defined in claim 1, wherein in process step (e) the mixture is spray-dried at a temperature of from 150°

to 450°

C.

6. A process as defined in claim 1, wherein the resulting dried catalyst is pelletized.