Aromatics isomerization using a dual-catalyst system

Patent metadata

Field	Value
Publication number	US-9309170-B2
Application number	US-201213649546-A
Country	US
Kind code	B2
Filing date	Oct 11, 2012
Priority date	Nov 14, 2011
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

This invention is drawn to a process for isomerizing a non-equilibrium mixture of xylenes and ethylbenzene which contain a substantial concentration of nonaromatics using a catalyst system which features the ability to both convert nonaromatics and to obtain an improved yield of para-xylene from the mixture relative to processes of the known art.

First claim

The invention claimed is:

1. A process for the conversion of a hydrocarbon feed mixture comprising a major concentration of nonequilibrium C 8 aromatics and a minor concentration of nonaromatics by contacting the mixture with a dual-catalyst system comprising a first catalyst consisting of a tungsten component and a second catalyst comprising from about 0.01 to about 0.2 mass-% on an elemental basis of at least one platinum-group metal component at hydrocarbon-conversion conditions comprising a temperature of about 300° to about 550° C., a pressure of about 100 kPa to 5 MPa and a liquid hourly space velocity of about 0.5 to 50 hr −1 with respect to the dual-catalyst system to obtain a converted product comprising a reduced concentration of ethylbenzene and a reduced concentration of nonaromatics than in the feed mixture.

2. The process of claim 1 wherein the concentration of nonaromatics is from about 0.5 to 10 mass-% of the feed mixture.

3. The process of claim 1 wherein the first catalyst comprises a layered sphere.

4. The process of claim 1 wherein the first and second catalysts are stacked sequentially.

5. The process of claim 1 wherein the catalyst system is a physical mixture of the first and second catalyst.

6. The process of claim 1 wherein the first and second catalysts are contained on the same catalyst particle.

7. The process of claim 6 wherein the first catalyst comprises a layer on the surface of the second catalyst.

8. A process for the conversion of a hydrocarbon feed mixture comprising a major concentration of nonequilibrium C 8 aromatics and a minor concentration of nonaromatics by contacting the mixture with a dual-catalyst system comprising a first catalyst consisting of a tungsten component and a second catalyst comprising from about 0.01 to about 0.2 mass-% on an elemental basis of at least one platinum-group metal component at hydrocarbon-conversion conditions comprising a temperature of about 300° to about 550° C., a pressure of about 100 kPa to 5 MPa and a liquid hourly space velocity of about 0.5 to 50 hr −1 with respect to the dual-catalyst system to obtain a converted product comprising a higher proportion of at least one xylene isomer, a reduced concentration of ethylbenzene and a reduced concentration of nonaromatics than in the feed mixture.

9. The process of claim 8 wherein the concentration of nonaromatics is from about 0.5 to 10 mass-% of the feed mixture.

10. The process of claim 8 wherein the first catalyst comprises a layered sphere.

11. The process of claim 8 wherein the first and second catalysts are stacked sequentially.

12. The process of claim 8 wherein the catalyst system is a physical mixture of the first and second catalyst.

13. The process of claim 8 wherein the first and second catalysts are contained on the same catalyst particle.

14. The process of claim 8 wherein the first catalyst comprises a layer on the surface of the second catalyst.

Assignees

• Uop Llc

Inventors

• Bogdan Paula L
• Johnson James A
• Gajda Gregory J
• Whitchurch Patrick C
• Frey Stanley J
• Spieker Wolfgang A

Classifications

• C07C2521/16

  Clays or other mineral silicates · CPC title

• C07C2523/36

  Rhenium · CPC title

• C07C2521/06

  Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof · CPC title

• C07C2523/14

  of germanium, tin or lead · CPC title

• C07C2523/46

  Ruthenium, rhodium, osmium or iridium · CPC title