Process for the regeneration of a supported noble metal catalyst

Patent metadata

Field	Value
Publication number	US-9687838-B2
Application number	US-201414899444-A
Country	US
Kind code	B2
Filing date	Jun 17, 2014
Priority date	Jun 17, 2013
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

A process for the regeneration of a supported noble metal catalyst comprising contacting the catalyst with a liquid aqueous system at a temperature in the range of from 90 to 160° C., wherein the pH of the aqueous system is outside the range of from 6 to 8, separating the aqueous system from catalyst; and subjecting the catalyst to calcination.

First claim

The invention claimed is:

1. A process for regenerating a supported noble metal catalyst, the process comprising
(a) separating the catalyst from a mixture (A) to obtain a separated catalyst (I);
(b) contacting the separated catalyst (I) with a liquid aqueous system at a temperature in a range of from 90 to 160° C. in a closed system under autogenous pressure, wherein a pH of the aqueous system is outside a range of from 6 to 8;
(c) separating the liquid aqueous system from the separated catalyst (I) to obtain a separated catalyst (II); and
(d) subjecting the separated catalyst (II) to calcination,
wherein the catalyst has been used in a process comprising
(i) providing a mixture comprising water, an organic solvent, and a hydroperoxypropanol; and
(ii) treating the mixture provided in (i) in a reactor under reducing conditions with hydrogen in the presence of the catalyst to obtain the mixture (A) comprising water, the organic solvent, and propylene glycol.

2. The process of claim 1 , wherein the mixture provided in (i) comprises the hydroperoxypropanol in an amount of from 0.1 to 1 weight-% based on a weight of the mixture.

3. The process of claim 1 , wherein the mixture provided in (i) further comprises an oxygenate in an amount of from 0.1 to 1 weight-% based on a weight of the mixture.

4. The process of claim 1 , wherein the mixture provided in (i) comprises water in an amount of from 10 to 40 weight-% and the organic solvent in an amount of from 55 to 85 weight-%, based on a weight of the mixture.

5. The process of claim 1 , wherein the organic solvent in the mixture provided in (i) is selected from the group consisting of methanol and acetonitrile.

6. The process of claim 1 , wherein the noble metal of the supported noble metal catalyst is selected from the group consisting of palladium, platinum, rhodium, iridium, osmium and a combination of two or more thereof.

7. The process of claim 1 , wherein the treating (ii) is carried out at a temperature in a range of from 25 to 120° C. and a pressure in a range of from 1 to 100 bar abs .

8. The process of claim 1 , wherein the contacting (b) is performed in the reactor of (ii) comprising the separated catalyst (I).

9. The process of claim 1 , wherein the contacting (b) is performed for a period of time in a range of from 0.1 to 10 h.

10. The process of claim 1 , wherein the pH of the liquid aqueous system in (b) is in a range of from 0 to 5.5.

11. The process of claim 1 , wherein the pH of the liquid aqueous system in (b) is in a range of from 8.5 to 14.

12. The process of claim 1 , wherein the separating (a) is performed by filtration, centrifugation, decantation, evaporation, or a combination of two or more thereof, and
wherein the separating (c) is performed by filtration, centrifugation, decantation, evaporation, or a combination of two or more thereof.

13. The process of claim 12 , wherein the separating (c) further comprises
washing the separated catalyst (I).

14. The process of claim 1 , wherein in (d), the separated catalyst (II) is subjected to the calcination at a temperature in a range of from 200 to 700° C.

15. The process of claim 1 , further comprising
(e) activating the catalyst obtained from (d).

16. The process of claim 1 , wherein the mixture provided in (i) is obtained by a process for epoxidizing propene comprising
reacting propene with hydrogen peroxide in the presence of the organic solvent and a titanium zeolite catalyst to obtain an epoxidation reaction mixture, and
separating propylene oxide from the epoxidation reaction mixture to obtain the mixture provided in (i).

17. The process of claim 1 , comprising employing the catalyst obtained from (d) as a catalyst in a process comprising (ii).

Assignees

• Basf Se
• Dow Global Technologies Llc

Inventors

• Heidemann Thomas
• Becker Barbara

Classifications

• B01J38/64

  using alkaline material; using salts · CPC title

• B01J38/48 Primary

  Liquid treating or treating in liquid phase, e.g. dissolved or suspended · CPC title

• B01J38/62

  organic · CPC title

• B01J38/02

  Heat treatment · CPC title

• B01J23/96

  of catalysts comprising metals, oxides or hydroxides of the noble metals · CPC title