Cyclization and fluid catalytic cracking systems and methods for upgrading naphtha

Patent metadata

Field	Value
Publication number	US-11965136-B2
Application number	US-202117150012-A
Country	US
Kind code	B2
Filing date	Jan 15, 2021
Priority date	Jan 15, 2021
Publication date	Apr 23, 2024
Grant date	Apr 23, 2024

Abstract

A process for upgrading a naphtha feed includes separating the naphtha feed into at least a light naphtha fraction, contacting the light naphtha fraction with hydrogen in the presence of at least one cyclization catalyst, and contacting the cyclization effluent with at least one cracking catalyst. Contacting the light naphtha fraction with hydrogen in the presence of at least one cyclization catalyst may produce a cyclization effluent comprising a greater concentration of naphthenes compared to the light naphtha fraction. Contacting the cyclization effluent with at least one cracking catalyst under conditions sufficient to crack at least a portion of the cyclization effluent may produce a fluid catalytic cracking effluent comprising light olefins, gasoline blending components, or both. A system for upgrading a naphtha feed includes a naphtha separation unit, a cyclization unit disposed downstream of the naphtha separation unit, and a fluid catalytic cracking unit disposed downstream of the cyclization unit.

First claim

What is claimed is:

1. A process for separating and upgrading a naphtha feed, the process comprising:
passing the naphtha feed to a naphtha separation unit that separates the naphtha feed into at least a light naphtha fraction and a heavy naphtha fraction;
passing the light naphtha fraction to a cyclization unit that contacts the light naphtha fraction with hydrogen in the presence of at least one cyclization catalyst to produce a cyclization effluent comprising a greater concentration of naphthenes compared to the light naphtha fraction, wherein the at least one cyclization catalyst comprises ultra-stable Y-type (USY) zeolite and platinum as an active phase metal supported on the USY zeolite, the cyclization catalyst comprises from 60 weight percent to 80 weight percent USY zeolite based on the total weight of the cyclization catalyst, and the cyclization unit operates at a temperature of 475° C., a hydrogen partial pressure of 0.3 MPa (3 bar), and a molar ratio of hydrogen to light naphtha fraction of 3; and
passing the cyclization effluent to a fluid catalytic cracking unit that contacts the cyclization effluent with at least one cracking catalyst at a temperature of from 650° C. to 700° C., a pressure of from 0.1 1VIPa to 1 1VIPa, and a weight ratio of the cracking catalyst to the cyclization effluent feed of from 1:2 to 1:30, where the contact of the cyclization effluent with the at least one cracking catalyst cracks at least a portion of the cyclization effluent to produce a fluid catalytic cracking effluent comprising light olefins, gasoline blending components, or both;
passing the heavy naphtha fraction to a naphtha reforming unit that contacts the heavy naphtha fraction with at least one reforming catalyst to undergo one or more reactions under conditions sufficient to produce a reformate effluent, wherein the at least one reforming catalyst consists of:
a precious metal selected from the group consisting of platinum,
palladium, and combinations thereof; and

a catalyst support selected from the group consisting of alumina, silica, titania, and combinations thereof.

2. The process of claim 1 , further comprising passing a portion of the fluid catalytic cracking effluent, at least a portion of the naphtha reformate, or both to a gasoline pool.

3. The process of claim 1 , further comprising passing a portion of the fluid catalytic cracking effluent, at least a portion of the naphtha reformate, or both to an aromatic recovery complex to produce benzene, toluene, xylene, or combinations of these.

4. The process of claim 1 , further comprising passing a supplemental FCC feed to the fluid catalytic cracking unit and contacting the supplemental FCC feed and the cyclization effluent with the at least one cracking catalyst to produce the fluid catalytic cracking effluent, where the supplemental FCC feed comprises vacuum gas oil, demetalli 7 ed oil, atmospheric residue, or combinations of these.

5. The process of claim 1 , further comprising contacting the naphtha feed with hydrogen in the presence of a desulfurization catalyst in a desulfurization unit prior to separating the naphtha feed into the light naphtha fraction and the heavy naphtha fraction, where the contacting causes at least a portion of sulfur components to be removed from the naphtha feed to produce a desulfurized naphtha feed.

6. The process of claim 5 , where the desulfurized naphtha feed comprises less than or equal to 0.5 parts per million by weight of sulfur compounds and less than or equal to 0.5 parts per million by of weight nitrogen compounds based on the total weight of the desulfurized naphtha feed.

7. The process of claim 1 , where the light naphtha fraction comprises constituents of the naphtha feed having boiling point temperatures less than or equal to 70 degrees Celsius.

8. The process of claim 1 , where the heavy naphtha fraction comprises constituents of the naphtha feed having boiling point temperatures greater than 70 degrees Celsius.

9. The process of claim 1 , where contacting the light naphtha fraction with hydrogen in the presence of at least one cyclization catalyst causes at least a portion of paraffin compounds in the light naphtha fraction to undergo a cyclization reaction to produce naphthenes.

10. The process of claim 1 , where the cyclization catalyst comprises from 0.01 weight percent to 40 weight percent platinum.

11. The process of claim 1 , where the light naphtha fraction is contacted with hydrogen in the presence of the cyclization catalyst at a liquid hourly space velocity ranging from 1 h −1 to 10 h −1 .

12. The process of claim 1 , further comprising:
contacting the naphtha feed with hydrogen in the presence of a desulfurization catalyst, where the contacting causes at least a portion of sulfur components to be removed from the naphtha feed to produce a desulfurized naphtha feed,
wherein the desulfurization catalyst comprises nickel, molybdenum, cobalt, or combinations of these and wherein the desulfurization catalyst further comprises a dopant comprising silicon.

13. The process of claim 1 , wherein the cyclization effluent comprises greater than 26 wt. % naphthenes based on the total weight of the cyclization effluent.

14. The process of claim 1 , wherein the naphtha feed comprises C 5 -C 6 drocarbons and the light naphtha fraction comprises at least 80% by weight of the C 5 -C 6 drocarbons of the naphtha feed.

15. The process of claim 1 , wherein the naphtha feed comprises C 7+ hydrocarbons and the heavy naphtha fraction comprises at least 80% by weight of the C 7+ hydrocarbons of the naphtha feed.

16. The process of claim 1 , the process further comprising:
separating the reformate effluent into at least a naphtha reformate effluent and a hydrogen effluent;
passing at least a portion of the naphtha reformate effluent and at least a portion of the fluid catalytic cracking effluent to an aromatic recovery complex; and
recovering a product comprising one or more of benzene, toluene, xylene, or combinations of thereof from the at least a portion of the naphtha reformate effluent and the at least a portion of the fluid catalytic cracking effluent in the aromatic recovery complex.

17. The process of claim 16 , the process further comprising:
passing the fluid catalytic cracking effluent to a fluid catalytic cracking separation unit;
separating the fluid catalytic cracking effluent into at least a light gas fraction, a light naphtha recycle fraction, an aromatic containing effluent, and a light olefin fraction, or combinations of these in the fluid catalytic cracking separation unit; and
passing the light naphtha recycle fraction to the fluid catalytic cracking unit.

18. The process of claim 17 , the process further comprising:
combining the light naphtha recycle fraction with the cyclization effluent upstream of the fluid catalytic cracking unit; and
passing the light naphtha and cyclization effluent to the fluid catalytic cracking unit.

Assignees

• Saudi Arabian Oil Co

Inventors

• Koseoglu Omer Refa

Classifications

• C10G63/08 Primary

  including at least one cracking step · CPC title

• C10G11/18

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

• C10G35/095

  containing crystalline alumino-silicates, e.g. molecular sieves {(C10G35/065 takes precedence)} · CPC title

• C10G45/02

  to eliminate hetero atoms without changing the skeleton of the hydrocarbon involved and without cracking into lower boiling hydrocarbons; Hydrofinishing · CPC title

• C10G63/04

  including at least one cracking step · CPC title