Process for producing LPG and BTX

Patent metadata

Field	Value
Publication number	US-10287518-B2
Application number	US-201515538447-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Dec 22, 2014
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

The invention relates to a process for producing LPG and BTX, comprising a) subjecting a mixed hydrocarbon feedstream to first hydrocracking in the presence of a first hydrocracking catalyst to produce a first hydrocracking product stream; b) separating the first hydrocracking product stream to provide at least a light hydrocarbon stream comprising at least C2 and C3 hydrocarbons, a middle hydrocarbon stream comprising C4 and/or C5 hydrocarbons and a heavy hydrocarbon stream comprising at least C6+ hydrocarbons and c) subjecting the heavy hydrocarbon stream to second hydrocracking to produce a second hydrocracking product stream comprising BTX, wherein the second hydrocracking is more severe than the first hydrocracking, wherein at least part of the middle hydrocarbon stream is recycled back to the first hydrocracking in step a).

First claim

The invention claimed is:

1. A process for producing LPG and BTX, comprising
a) subjecting a mixed hydrocarbon feedstream to first hydrocracking in the presence of a first hydrocracking catalyst to produce a first hydrocracking product stream;
b) separating the first hydrocracking product stream to provide at least
a light hydrocarbon stream comprising at least C2 and C3 hydrocarbons,
a middle hydrocarbon stream comprising C4 and/or C5 hydrocarbons and
a heavy hydrocarbon stream comprising at least C6+ hydrocarbons and
c) subjecting the heavy hydrocarbon stream to second hydrocracking in the presence of a second hydrocracking catalyst to produce a second hydrocracking product stream comprising BTX, wherein the second hydrocracking is more severe than the first hydrocracking,
wherein at least part of the middle hydrocarbon stream is recycled back to the first hydrocracking in step a); and
wherein the first hydrocracking is performed under conditions comprising a temperature of 250-580° C. and wherein the second hydrocracking is performed under conditions comprising a temperature of 300-580° C.

2. The process according to claim 1 , wherein the first hydrocracking is a hydrocracking process suitable for converting a hydrocarbon feed comprising naphthenic and paraffinic hydrocarbon compounds to a stream comprising LPG and aromatic hydrocarbons.

3. The process according claim 1 , wherein the first hydrocracking catalyst is a catalyst containing one or more metals of group VIII, VIB or VIIB of the periodic classification of elements deposited on a carrier.

4. The process according to claim 1 , wherein the second hydrocracking product stream is substantially free from non-aromatic C6+ hydrocarbons.

5. The process according to claim 1 , wherein the second hydrocracking is performed using a hydrocracking catalyst comprising 0.01-1 wt-% hydrogenation metal in relation to the total catalyst weight and a zeolite having a pore size of 5-8 Å and a silica (SiO 2 ) to alumina (Al 2 O 3 ) molar ratio of 5-200 under conditions comprising a pressure of 0.3-5 MPa gauge and a Weight Hourly Space Velocity (WHSV) of 0.1-15 h −1 .

6. The process according to claim 1 , wherein the mixed hydrocarbon feedstream comprises naphtha.

7. The process according to claim 1 , wherein H 2 or H 2 and C1 hydrocarbon are separated from the first hydrocracking product stream before the separation between the light, middle and heavy hydrocarbon streams.

8. The process according to claim 1 , wherein the separation between the light hydrocarbon stream and the middle hydrocarbon stream is performed to separate between C3 hydrocarbon and iC4 hydrocarbon, between iC4 hydrocarbon and nC4 hydrocarbon or between nC4 hydrocarbon and C5 hydrocarbon.

9. The process according to claim 1 , wherein the separation between the middle hydrocarbon stream and the heavy hydrocarbon stream is performed to separate between iC4 hydrocarbon and nC4 hydrocarbon, between nC4 hydrocarbon and C5 hydrocarbon or between C5 hydrocarbon and C6 hydrocarbon.

10. The process according to claim 1 , wherein at least part of non-recycled C4 hydrocarbon from the middle hydrocarbon stream is subjected to a further step selected from the group consisting of isomerization, butane dehydrogenation (non-oxidative and oxidative), reaction with methanol and reaction with ethanol and combinations thereof.

11. The process according to claim 1 , wherein
the separation between the light hydrocarbon stream and the middle hydrocarbon stream is performed to separate between C3 hydrocarbon and iC4 hydrocarbon;
the separation between the middle hydrocarbon stream and the heavy hydrocarbon stream is performed to separate C5 hydrocarbon and C6 hydrocarbon;
step b) involves separating between the C4 hydrocarbon of the middle hydrocarbon stream and the C5 hydrocarbon of the middle hydrocarbon stream;
at least part of the C5 hydrocarbon in the middle hydrocarbon stream is recycled back to the first hydrocracking in step a); and
at least part of the C4 hydrocarbon in the middle hydrocarbon stream is subjected to a further step selected from the group consisting of isomerization, butane dehydrogenation (non-oxidative and oxidative), reaction with methanol and reaction with ethanol and combinations thereof.

12. The process according to claim 1 , wherein C4-hydrocarbon in the second hydrocracking product stream is separated from the second hydrocracking product stream to be recycled back to the separation of step b) or combined with the light hydrocarbon stream.

13. The process according to claim 1 , wherein the amount of methane in the first hydrocracking product stream is at most 5 wt %.

14. The process according to claim 1 , wherein the amount of the C4 and C5 hydrocarbons in the at least part of the middle hydrocarbon stream is at least 70 wt %.

15. The process according to claim 1 , wherein the temperature is 425-580° C.

16. The process according to claim 6 , wherein the mixed hydrocarbon feed stream has a boiling point range of 20−200° C.

Assignees

• Sabic Global Technologies Bv

Inventors

• Oprins Arno Johannes Maria
• Davies Andrew P
• Ward Andrew Mark
• Wong Kae Shin
• Aramburo Luis
• Van Iersel Maikel

Classifications

• C10G65/18

  including only cracking steps · CPC title

• C10G2300/301

  Boiling range · CPC title

• C10G2400/30

  Aromatics · CPC title

• C10G69/02

  plural serial stages only · CPC title

• C10G2400/20

  C2-C4 olefins · CPC title