Methods for producing aromatics and olefins

Patent metadata

Field	Value
Publication number	US-10781382-B2
Application number	US-201615774206-A
Country	US
Kind code	B2
Filing date	Nov 7, 2016
Priority date	Nov 12, 2015
Publication date	Sep 22, 2020
Grant date	Sep 22, 2020

Abstract

The presently disclosed subject matter provides methods for producing olefins and/or aromatics from coker naphtha. In a non-limiting embodiment, a method for producing aromatics includes hydrogenating the coker naphtha stream in the presence of a first catalyst to remove diolefins and sulfur, if any, to obtain a hydrogenated stream and subjecting the hydrogenated stream to aromatization in the presence of a second catalyst to produce an aromatic-rich stream that includes benzene, toluene and xylene. In certain embodiments, a method for producing olefins includes hydrogenating the coker naphtha stream in the presence of a first catalyst to remove diolefins and sulfur, if any, to obtain a hydrogenated stream and subjecting the hydrogenated stream to catalytic cracking in the presence of a second catalyst to produce an olefin-rich stream that includes ethylene, propylene and aromatics.

First claim

The invention claimed is:

1. A method for producing aromatics from a coker naphtha stream, the method comprising:
(a) hydrogenating the coker naphtha stream containing coker naphtha to a certain degree, wherein the coker naphtha has a boiling point of from about 25° C. to 85° C. in the presence of a first catalyst to remove diolefins and sulfur to obtain a hydrogenated stream; and
(b) subjecting the hydrogenated stream to dehydrocycloligomerization in the presence of a second catalyst to produce an aromatic-rich stream comprising benzene, toluene, and xylene, wherein the coker naphtha stream further comprises from about 0.5 wt % to about 5 wt % aromatics, and wherein the second catalyst has a metal oxide loading of about 0.2 wt % to about 1.5 wt % and is selected from the group consisting of Ga/Pt/Ge/ZSM-5, Pt/Ge/ZSM-5 and Ni—W/Ga/ZSM-5, or the second catalyst is Ga/Nd/ZSM-5.

2. The method of claim 1 , wherein the second catalyst comprises from about 0.025-0.2 wt. % of a promoter metal selected from the group consisting of Ga, Ge, Nd and/or W.

3. The method of claim 1 , wherein the aromatic-rich stream comprises at least about 40% by weight of aromatic compounds.

4. The method of claim 1 , further comprising hydrodealkylating the aromatic-rich stream in the presence of a third catalyst and hydrogen to produce a benzene-rich stream.

5. The method of claim 1 , further comprising mild hydrocracking the aromatic-rich stream in the presence of a third catalyst and hydrogen to produce a benzene-rich stream, wherein the mild hydrocracking is conducted at a temperature from about 400 to about 550° C.

6. The method of claim 5 , wherein the mild hydrocracking is conducted at a pressure of 5 bar to about 20 bar.

7. The method of claim 6 , further comprising mild hydrocracking the benzene-rich stream to produce a stream comprising greater than or equal to about 99% benzene by weight.

8. The method of claim 1 , wherein the second catalyst is selected from the group consisting of Ga/Nd/ZSM-5 and Ni—W/Ga/ZSM-5.

9. A method for producing aromatics from a coker naphtha stream containing coker naphtha, the method comprising:
(a) removing silica and particulates from the coker naphtha stream to obtain a pretreated coker naphtha stream;
(b) hydrogenating the pretreated coker naphtha stream in the presence of a first catalyst to remove diolefins and sulfur to obtain a hydrogenated stream comprising olefins; and
(c) subjecting the hydrogenated stream to an aromatization process in the presence of a second catalyst to produce an aromatic-rich stream comprising at least about 40% by weight of aromatic compounds;
wherein the coker naphtha has a boiling point of from about 25° C. to 85° C. and comprises silica and particulates;
wherein the second catalyst has a metal oxide loading of about 0.2 wt % to about 1.5 wt % and is selected from the group consisting of Ga/Pt/Ge/ZSM-5, Pt/Ge/ZSM-5 and Ni—W/Ga/ZSM-5, or the second catalyst is Ga/Nd/ZSM-5; and
wherein the coker naphtha stream comprises from about 0.5 wt % to about 5 wt % aromatics.

10. The method of claim 9 , further comprising:
(d) hydrodealkylating the aromatic-rich stream in the presence of a third catalyst to produce a benzene-rich stream; and
(e) distilling the benzene-rich stream to obtain a purified product stream comprising greater than or equal to about 99% benzene.

11. A method for producing olefins from a coker naphtha stream containing diolefins and sulfur, the method comprising:
(a) hydrogenating the coker naphtha stream, wherein the coker naphtha stream contains coker naphtha, wherein the coker naphtha has a boiling point of from about 25° C. to 85° C. in the presence of a first catalyst to remove the diolefins and the sulfur to obtain a hydrogenated stream; and
(b) subjecting the hydrogenated stream to catalytic cracking in the presence of a second catalyst at a pressure from about 50 to about 300 kPa to produce an olefin-rich stream comprising ethylene, propylene and aromatics, wherein the second catalyst has a metal oxide loading of about 2 wt % to about 10 wt % and is selected from the group consisting of Ga/Pt/Ge/ZSM-5, Pt/Ga/ZSM-5, Pt/Ge/ZSM-5 and Ni—W/Ga/ZSM-5, or the second catalyst is Ga/Nd/ZSM-5;
wherein the method further comprises removing silica and particulates from the coker naphtha stream prior to hydrogenation; and
wherein the coker naphtha stream comprises from about 0.5 wt % to about 5 wt % aromatics.

12. The method of claim 11 , wherein the second catalyst is selected from the group consisting of Ga/Nd/ZSM-5 and Ni—W/Ga/ZSM-5.

13. The method of claim 11 , wherein the olefins-rich stream comprises greater than about 55% of olefins.

14. The method of claim 9 , further comprising the steps of:
(d) hydrodealkylating the aromatic-rich stream in the presence of a third catalyst to produce a benzene-rich stream; and
(e) distilling the benzene-rich stream to obtain a purified product stream comprising greater than or equal to about 99% benzene.

15. The method of claim 1 , further comprising extracting benzene from the aromatic rich stream to obtain a benzene rich stream.

16. The method of claim 1 , wherein the coker naphtha stream further comprises from about 20 wt % to about 70 wt % paraffins, from about 20 wt % to about 45 wt % olefins, from about 0.01 wt % to about 3 wt % diolefins and from about 5 wt % to about 15 wt % naphthenes.

Assignees

• Sabic Global Technologies Bv

Inventors

• Dongara Rajeshwer
• Mathure Pankaj
• Ahmed Mohammad Basheer
• Bv Venugopal

Classifications

• C10G9/30

  according to the "moving bed" method · CPC title

• C10G63/04

  including at least one cracking step · CPC title

• C10G47/30

  according to the "fluidised-bed" technique · CPC title

• C10G35/085

  containing platinum group metals or compounds thereof · CPC title

• C10G45/38

  in combination with chromium, molybdenum or tungsten metals, or compounds thereof · CPC title