Processes for rejuvenating catalysts

Patent metadata

Field	Value
Publication number	US-10994268-B2
Application number	US-201815947986-A
Country	US
Kind code	B2
Filing date	Apr 9, 2018
Priority date	May 3, 2017
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

Disclosed are processes for rejuvenating catalysts comprising at least one Group 10 metal and a microporous crystalline metallosilicate, and hydrocarbon conversion processes including such rejuvenation processes. In an aspect, the rejuvenation process comprises contacting a deactivated catalyst comprising at least one Group 10 metal and a microporous crystalline metallosilicate with an oxygen-containing gaseous stream under conditions comprising a temperature ranging from about 250° C. to about 375° C. and a pressure of up to about 100 bar. In a further aspect, the rejuvenation process comprises contacting a deactivated catalyst comprising at least one Group 10 metal, at least one rare earth metal, and a microporous crystalline metallosilicate with an oxygen-containing gaseous stream under conditions comprising a temperature ranging from about 250° C. to about 500° C. and a pressure of up to about 100 bar.

First claim

The invention claimed is:

1. A process for rejuvenating a deactivated catalyst comprising at least one Group 10 metal and a microporous crystalline metallosilicate, the process comprising the steps of:
(a) contacting the catalyst with an oxygen-containing gaseous stream under conditions comprising a temperature ranging from about 250° C. to about 375° C. and a pressure of up to about 100 bar; and
(b) optionally, reducing the catalyst to obtain a rejuvenated catalyst.

2. The process claim 1 , wherein the at least one Group 10 metal comprises platinum.

3. The process of any claim 1 , wherein the catalyst further comprises one or more additional metals selected from the group consisting of Group 1 metals, Group 2 metals, Group 8 metals, Group 9 metals, Group 11 metals, and mixtures or combinations thereof.

4. The process of claim 3 , wherein the one or more additional metals is selected from the group consisting of sodium, copper, silver, and mixtures or combinations thereof.

5. The process of claim 4 , wherein the contacting temperature of step (a) ranges from about 300° C. to about 350° C.

6. The process of claim 1 , wherein the microporous crystalline metallosilicate is an aluminosilicate selected from the group consisting of ZSM-5, ZSM-11, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-50, ZSM-57, ZSM-58, a MCM-22 family material, and mixtures or combinations of two or more thereof.

7. The process of claim 6 , wherein the aluminosilicate is ZSM-5.

8. The process of claim 1 , wherein the catalyst further comprises a binder comprising one or more of silica, titania, zirconia, metal silicates of Group 1 or Group 13 of the Periodic Table, carbides, nitrides, aluminum phosphate, aluminum molybdate, aluminate, surface passivated alumina, and mixtures thereof.

9. The process of claim 1 , wherein step (b) comprises contacting the catalyst with a hydrogen-containing gaseous stream under conditions comprising a temperature ranging from about 200° C. to about 800° C. and a pressure of up to about 100 bar.

10. The process of claim 1 , further comprising the additional step of: (c) contacting the catalyst with a hydrogen-containing gaseous stream prior to the contacting of step (a), wherein the catalyst is contacted with the hydrogen-containing gaseous stream under conditions comprising a temperature ranging from about 200° C. to about 800° C. and a pressure of up to about 100 bar.

11. The process of claim 1 , wherein the oxygen-containing gaseous stream comprises a member selected from the group consisting of O 2 , O 3 , nitrogen oxides, CO 2 , and mixtures or combinations thereof.

12. The process of claim 11 , wherein the contacting of step (a) comprises:
(i) contacting the catalyst with a first gaseous stream comprising CO 2 ; and
(ii) subsequently contacting the catalyst with a second gaseous stream comprising a member selected from the group consisting of O 2 , O 3 , nitrogen oxides, and mixtures or combinations thereof.

13. The process of claim 1 , wherein the oxygen-containing gaseous stream has an oxygen concentration ranging from about 0.1 volume percent to about 20 volume percent.

14. The process of claim 1 , wherein the oxygen-containing gaseous stream is supplied to the contacting of step (a) at a WHSV ranging from about 1 to about 10,000.

15. The process of claim 1 , further comprising the step of increasing the temperature during the contacting of step (a).

16. The process of claim 1 , further comprising the step of increasing the oxygen partial pressure and/or oxygen concentration of the oxygen-containing gaseous stream during the contacting of step (a).

17. The process of claim 1 , wherein the contacting of step (a) has a time duration of about 5 hours or less.

18. A process for rejuvenating a deactivated catalyst comprising at least one Group 10 metal, at least one rare earth metal, and a microporous crystalline metallosilicate, the process comprising the steps of:
(a) contacting the catalyst with an oxygen-containing gaseous stream under conditions comprising a temperature ranging from about 250° C. to about 500° C. and a pressure of up to about 100 bar; and
(b) optionally, reducing the catalyst to obtain a rejuvenated catalyst.

19. The process of claim 18 , wherein the contacting of step (a) comprises:
(i) contacting the catalyst with a first gaseous stream comprising CO 2 ; and
(ii) subsequently contacting the catalyst with a second gaseous stream comprising a member selected from the group consisting of O 2 , O 3 , nitrogen oxides, and mixtures or combinations thereof.

20. The process of claim 18 , further comprising the step of increasing the oxygen partial pressure and/or oxygen concentration of the oxygen-containing gaseous stream during the contacting of step (a).

21. A process for the chemical conversion of a hydrocarbon feedstock, the process comprising the steps of:
(I) contacting a hydrocarbon feedstock with a catalyst comprising at least one Group 10 metal and a microporous crystalline metallosilicate in a reaction zone to form a hydrocarbon reaction product;
(II) forming deactivated catalyst from the catalyst;
(III) rejuvenating the deactivated catalyst in accordance with the process of claim 1 ; and
(IV) optionally, periodically regenerating the deactivated catalyst.

22. The process of claim 21 , further comprising the additional step of (V) purging any combustible gas, including hydrocarbon feedstock and hydrocarbon reaction product, from the deactivated and/or rejuvenated catalyst.

23. The process of claim 21 , wherein the rejuvenation of step (III) is performed in the reaction zone.

24. The process of claim 21 , wherein the rejuvenation of step (III) is performed in a separate rejuvenation zone apart from the reaction zone.

25. The process of claim 21 , wherein the chemical conversion comprises one or more of the following:
i. the conversion of acyclic C 5 hydrocarbons to cyclic C 5 hydrocarbons;
ii. the conversion of acyclic C 6+ hydrocarbons to aromatic C 6+ hydrocarbons;
iii. the conversion of C 2 -C 5 hydrocarbons to C 6+ aromatic; and/or
iv. the dehydrogenation of paraffins to olefins and/or dienes.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Iaccino Larry L
• Bao Xiaoying
• Bedard Jeremy W

Classifications

• B01J38/18

  with subsequent reactive gas treating · CPC title

• C07C2529/46

  Iron group metals or copper · CPC title

• C07C2529/44

  Noble metals · CPC title

• C07C5/333

  Catalytic processes · CPC title

• C07C5/373

  with simultaneous isomerisation · CPC title