Process for the regeneration of a supported noble metal catalyst

Patent metadata

Field	Value
Publication number	US-2016144353-A1
Application number	US-201414899444-A
Country	US
Kind code	A1
Filing date	Jun 17, 2014
Priority date	Jun 17, 2013
Publication date	May 26, 2016
Grant date	—

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

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., 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 a closed system under autogenous pressure.

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

10 . 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.

11 . 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.

12 . 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.

13 . 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.

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

15 . 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.

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

17 . 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).

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

19 . A regenerated supported noble metal catalyst, obtained by the process according to claim 1 .

20 . (canceled)

21 . The regenerated supported noble metal catalyst of claim 19 ,
wherein in a process for hydrogenating hydroperoxypropanol, the regenerated catalyst exhibits a differential conversion rate of at most 5; wherein the differential conversion rate is defined as a difference in percentage between (I) a conversion rate based on hydroperoxypropanol in said process for hydrogenating hydroperoxypropanol in which the regenerated catalyst is used as catalyst, and (II) a conversion rate based on hydroperoxypropanol in said process for hydrogenating hydroperoxypropanol in which a respective fresh catalyst is used as catalyst; and wherein said process for hydrogenating hydroperoxypropanol according to (II) is carried out under otherwise identical hydrogenation conditions as compared with the process for hydrogenating hydroperoxypropanol according to (I).

Assignees

• Basf Se
• Dow Global Technologies Llc

Inventors

• Heidemann Thomas
• Becker Barbara

Classifications

• B01J38/62

  organic · CPC title

• C07C29/157

  containing platinum group metals or compounds thereof · CPC title

• B01J38/02

  Heat treatment · CPC title

• Y02P20/584

  Recycling of catalysts · CPC title

• B01J38/66

  using ammonia or derivatives thereof · CPC title