Method for generating core-shell catalysts

Abstract

In particular, this invention provides an improved eggshell catalyst having high pore volume and high wear resistance. [Solution] A method for producing a core-shell catalyst is provided, comprising the step of coating the outermost surface of a molded geometric support with a catalytically active multi-element oxide or powder P and one or more liquid binders, wherein the powder P is converted to a catalytically active multi-element oxide by heat treatment after coating, the coating is carried out in a horizontal mixer, and the Froude number during coating in the horizontal mixer is 0.0160 to 0.1200.

Claims

1. A method for producing an eggshell catalyst, wherein the outer surface of a geometrically shaped support a) A process of coating with one or more catalytically active multi-element oxides and one or more liquid binders, wherein the binder is later removed, or b) A step of coating with one or more powders P and one or more liquid binders, wherein the powders P are converted into one or more catalytically active multi-element oxides by heat treatment after coating. A method comprising the following, wherein the coating is carried out in a horizontal mixer, and the fluid number during coating in the horizontal mixer is 0.0040 to 0.1200.

2. The method according to claim 1, wherein the number of fluids in the coating in a horizontal mixer is 0.0160 to 0.0600.

3. The method according to claim 1 or 2, wherein the diameter of the mixing drum of the horizontal mixer is 0.5 to 2.5 m.

4. The method according to any one of claims 1 to 3, wherein the length of the mixing drum of the horizontal mixer is 0.25 to 1.5 m.

5. The method according to any one of claims 1 to 4, wherein a hollow cylindrical geometric support having a length of 3 to 8 mm, an outer diameter of 4 to 8 mm, and a wall thickness of 1 to 2 mm is used as the geometric support.

6. The method according to any one of claims 1 to 5, wherein the eggshell catalyst has an active composition content of 5% to 50% by mass relative to the total composition.

7. The method according to any one of claims 1 to 6, wherein 0.05 to 0.5 kg / kg of liquid binder is used in the coating with respect to the active composition.

8. The method according to any one of claims 1 to 7, wherein the coating period is 0.5 to 10 minutes per 1% by mass of the active composition content.

9. The method according to any one of claims 1 to 8, wherein the catalytically active multi-element oxide or powder P comprises the elements Mo, V and optionally W, or the elements Mo, Bi and optionally Fe.

10. The catalytically active multi-element oxide or powder P contains the elements Mo, W, V, Cu, and optionally Sb, and the ratio of the elements is given by general formula (I) Mo 12 W a V b Cu c Sb d (I) [In the formula, a=0.4～5.0、 b=1.0～6.0、 c=0.2～2.4、 d=0.0～2.0] The method according to any one of claims 1 to 9, wherein the molar ratio of element Mo to the total amount of all non-oxygen elements is 5 to 95 mol%.

11. An eggshell catalyst comprising a geometrically shaped support and one or more catalytically active multi-element oxides coated on the outer surface of the geometrically shaped support, which can be obtained by the method described in claims 1 to 10, wherein the pore volume and active composition content are as follows: PV / AM 0.55 > 0.140 An eggshell catalyst that satisfies the following conditions: [wherein PV is pore volume (ml / g) and AM is the active composition content (mass%)], the pore volume is determined after binder removal, the abrasion level is less than 5.5 mass%, and the abrasion material is determined before binder removal.

12. The pore volume and active composition content meet the following conditions: PV / AM 0.55 > 0.155 The eggshell catalyst according to claim 11, which satisfies the following conditions: [wherein PV is pore volume (ml / g) and AM is the active composition content (mass%)] and has an abrasion level of less than 2.5 mass%.

13. The eggshell catalyst according to claim 11 or 12, wherein a hollow cylindrical geometric support with a length of 3 to 8 mm, an outer diameter of 4 to 8 mm, and a wall thickness of 1 to 2 mm is used.

14. The eggshell catalyst according to any one of claims 10 to 13, wherein the eggshell catalyst has an active composition content of 5% to 50% by mass relative to the total composition.

15. A method for heterogeneous catalytic partial gas-phase oxidation in a stationary catalyst bed, wherein the stationary catalyst bed comprises the eggshell catalyst described in any one of claims 11 to 14.

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