Detergent alkylation catalyst regeneration effluent recycle

Patent metadata

Field	Value
Publication number	US-10427148-B2
Application number	US-201816058841-A
Country	US
Kind code	B2
Filing date	Aug 8, 2018
Priority date	May 19, 2016
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

A process for the regeneration of a catalyst is presented. The catalyst is in a reactor for use in benzene alkylation, and periodically needs to be regenerated. The reactor is taken off-line, and a regenerant is passed through the reactor, producing an effluent stream. A portion of the effluent stream is recycled through the reactor without passing through a clean-up process.

First claim

The invention claimed is:

1. A process for the regeneration of an alkylation reactor, comprising:
taking an alkylation reactor unit off-line to create an off-line reactor, wherein the alkylation reactor unit comprises an alkylation catalyst and is operated to produce linear alkylbenzene by the alkylation of benzene with olefins;
passing a regenerant stream comprising an aromatic to an inlet port of the off-line reactor to regenerate the alkylation catalyst and generate a regenerant effluent, during a regeneration cycle; and
recycling a portion of the regenerant effluent directly to the inlet port of the off-line reactor, wherein the portion is greater than 10 vol % of the regenerant effluent.

2. The process of claim 1 wherein the portion is between 50 vol % and 95 vol % of the regenerant effluent.

3. The process of claim 2 wherein the portion is between 75 vol % and 85 vol % of the regenerant effluent.

4. The process of claim 1 wherein a mass flux through the off-line reactor is between 40 kg/hr/m 2 and 500 kg/hr/m 2 .

5. The process of claim 4 wherein the mass flux through the off-line reactor is between 250 kg/hr/m 2 and 400 kg/hr/m 2 .

6. The process of claim 1 wherein the off-line reactor is purged with the regenerant stream.

7. The process of claim 6 wherein, after being purged with the regenerant, the off-line reactor is heated to a regeneration temperature to regenerate the alkylation catalyst and generate the regenerant effluent.

8. The process of claim 7 wherein the regeneration temperature is between 200° C. and 300° C.

9. The process of claim 7 wherein, after regenerating the alkylation catalyst and generating the regenerant effluent, the off-line reactor is cooled to a process temperature.

10. The process of claim 9 wherein, after being cooled to the process temperature, the off-line reactor is placed on-line for a process cycle.

11. The process of claim 1 further comprising passing a second portion of the regenerant effluent stream to a transalkylation reaction unit.

12. The process of claim 11 wherein the second portion is less than 50 vol % of the regenerant effluent stream.

13. The process of claim 1 wherein the regenerant is benzene.

14. The process of claim 1 wherein the regeneration cycle is between 1 and 72 hours.

15. A process for the production of linear alkylbenzenes:
passing a feedstream comprising unbranched and lightly branched olefins to an on-stream alkylation reaction unit comprising an alkylation catalyst;
passing an aromatic stream comprising benzene to the on-stream alkylation reaction unit to react with the olefins in the feedstream to generate an effluent stream comprising linear alkylbenzenes;
after a process cycle, taking the on-stream alkylation reaction unit off-line to create an off-stream alkylation reaction unit;
passing a regenerant stream comprising an aromatic to the off-stream alkylation reaction unit during a regeneration cycle, thereby regenerating the alkylation catalyst and generating a regenerant effluent stream; and
recycling a portion of the regenerant effluent stream directly to the off-stream alkylation reaction unit, wherein the portion of the regenerant effluent stream is greater than 20% of the regenerant effluent stream.

16. The process of claim 15 wherein the portion is between 75 vol % and 85 vol % of the regenerant effluent stream.

17. The process of claim 16 wherein the mass flux through the off-line reactor is between 250 kg/hr/m 2 and 400 kg/hr/m 2 .

18. The process of claim 15 wherein the feedstream comprises unbranched and lightly branched olefins having from 8 to 16 carbon atoms.

19. The process of claim 15 wherein the regeneration cycle is between 1 and 72 hours.

20. The process of claim 15 further comprising passing a second portion of the regenerant effluent stream to a transalkylation reaction unit.

Assignees

• Uop Llc

Inventors

• Sohn Stephen W
• Luebke Charles P
• Pieper Jeffrey L

Classifications

• C07C6/06

  at a cyclic carbon-to-carbon double bond · CPC title

• B01J29/90

  Regeneration or reactivation · CPC title

• B01J38/04

  Gas or vapour treating; Treating by using liquids vaporisable upon contacting spent catalyst · CPC title

• Y02P20/584

  Recycling of catalysts · CPC title

• B01J19/24

  Stationary reactors without moving elements inside (B01J19/08, B01J19/26 take precedence; with stationary particles B01J8/02) · CPC title