PROCESS FOR ISOMERIZING A FEED STREAM INCLUDING ONE OR MORE C4-C6 HYDROCARBONS

• US 20120184793A1
• Filed: 01/13/2011
• Published: 07/19/2012
• Est. Priority Date: 01/13/2011
• Status: Active Grant

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: Shecterle, David J.
• Granted Patent: US 8,692,046 B2
• Time in Patent Office: Days
• US Class Current: 585/738
• CPC Class Codes: C07C 5/2754 with metals
• CPC Class Codes: C10G 2300/104 Light gasoline having a boiling range of about 20 - 100 °C
• CPC Class Codes: C10G 2300/305 Octane number, e.g. motor octane number [MON], research octane number [RON]
• CPC Class Codes: C10G 2400/02 Gasoline
• CPC Class Codes: C10G 45/62 containing platinum group metals or compounds thereof

Abstract

One exemplary embodiment can be a process for isomerizing a feed stream including one or more C4-C6 hydrocarbons. The process may include contacting the feed stream in an isomerization reaction zone with an isomerization catalyst at isomerization conditions to produce an isomerization zone effluent; passing at least a portion of the isomerization zone effluent to a stabilizer zone and recovering a stabilizer overhead stream, a bottom stream, and a stripper feed stream; passing the stripper feed stream to a stripping zone and separating the stripper feed stream into a stripper overhead stream and a stripper bottom stream; and recycling at least a portion of the stripper bottom stream to a deisopentanizer zone and passing a stream from the deisopentanizer zone to the isomerization reaction zone. Usually, the stabilizer overhead stream includes one or more C5⁻ hydrocarbons, the bottom stream includes at least about 85%, by weight, one or more C6⁺ hydrocarbons, and a stripper feed stream including at least about 10%, by weight, one or more C5⁺ hydrocarbons. Often, a stripper overhead stream includes at least about 5%, by weight, one or more C4⁻ hydrocarbons and a stripper bottom stream includes at least about 90%, by weight, one or more C5⁺ hydrocarbons.

Claims

1. A process for isomerizing a feed stream comprising one or more C4-C6 hydrocarbons, comprising:

A) contacting the feed stream in an isomerization reaction zone with an isomerization catalyst at isomerization conditions to produce an isomerization zone effluent;

B) passing at least a portion of the isomerization zone effluent to a stabilizer zone and recovering a stabilizer overhead stream comprising one or more C5⁻

hydrocarbons, a bottom stream comprising at least about 85%, by weight, one or more C6⁺ hydrocarbons, and a stripper feed stream comprising at least about 10%, by weight, one or more C5⁺ hydrocarbons;

C) passing the stripper feed stream to a stripping zone and separating the stripper feed stream into a stripper overhead stream comprising at least about 5%, by weight, one or more C4⁻

hydrocarbons and a stripper bottom stream comprising at least about 90%, by weight, one or more C5⁺ hydrocarbons; and

(D) recycling at least a portion of the stripper bottom stream to a deisopentanizer zone and passing a stream from the deisopentanizer zone to the isomerization reaction zone.

2. The process according to claim 1, wherein the isomerization reaction zone comprises a chlorided platinum alumina catalyst or a sulfated zirconia catalyst.

3. The process according to claim 1, wherein the isomerization reaction zone comprises a catalyst, in turn, comprising a support comprising a sulfated oxide or hydroxide of at least one element of titanium, zirconium, halfnium, and dubnium;

a first component of at least one element of a lanthanide series and yttrium; and

a second component of at least one element of platinum, palladium, ruthenium, rhodium, iridium, and osmium.

4. The process according to claim 1, wherein the isomerization reaction zone comprises a catalyst, in turn, comprising an alumina, a platinum, and a chloride.

5. The process according to claim 1, wherein the stripping zone comprises a stripper column, and the stripper bottom stream upon exiting the stripper column is at a temperature of about 115-about 160°

C.

6. The process according to claim 5, wherein the stabilizer zone comprises a stabilizer column, and the bottom stream exiting the stabilizer column is at a temperature of about 140-about 210°

C.

7. The process according to claim 6, wherein the stabilizer column operates at a pressure of about 790-about 2,100 kPa.

8. The process according to claim 1, wherein the stabilizer zone comprises a stabilizer column and a receiver wherein the receiver collects an overhead stream from the stabilizer column, and at least a portion of the stripper feed stream is provided from the receiver.

9. The process according to claim 8, wherein the stripper feed stream is withdrawn from a tray at a top third of the stabilizer column.

10. The process according to claim 1, wherein the deisopentanizer zone further comprises a deisopentanizer column, and the process further comprises withdrawing an overhead stream comprising at least about 85%, by weight, one or more C5 hydrocarbons from the deisopentanizer column.

11. A process for isomerizing a feed stream comprising one or more C4-C6 hydrocarbons, comprising:

A) contacting the feed stream in an isomerization reaction zone with an isomerization catalyst at isomerization conditions to produce an isomerization zone effluent;

B) passing at least a portion of the isomerization zone effluent to a stabilizer column and recovering a stabilizer overhead stream comprising one or more C5⁻

hydrocarbons, and a bottom stream comprising at least about 85%, by weight, one or more C6⁺ hydrocarbons;

C) passing the stabilizer overhead stream to a receiver;

D) withdrawing a receiver bottom stream from the receiver and providing at least a portion as a stripper feed stream comprising at least about 10%, by weight, one or more C5⁺ hydrocarbons; and

E) recycling a stripper bottom stream comprising at least about 90%, by weight, one or more C5⁺ hydrocarbons to a deisopentanizer zone and passing a stream from the deisopentanizer zone to the isomerization reaction zone.

12. The process according to claim 11, wherein the isomerization reaction zone comprises a catalyst, in turn, comprising a support comprising a sulfated oxide or hydroxide of at least one element of titanium, zirconium, halfnium, and dubnium;

a first component of at least one element of a lanthanide series and yttrium; and

a second component of at least one element of platinum, palladium, ruthenium, rhodium, iridium, and osmium.

13. The process according to claim 11, wherein the isomerization reaction zone comprises a catalyst, in turn, comprising an alumina, a platinum, and a chloride.

14. The process according to claim 11, wherein the stripper bottom stream upon exiting a stripper column is at a temperature of about 115-about 160°

C.

15. A process for isomerizing a feed stream comprising one or more C4-C6 hydrocarbons, comprising:

A) contacting the feed stream in an isomerization reaction zone with an isomerization catalyst at isomerization conditions to produce an isomerization zone effluent;

B) passing at least a portion of the isomerization zone effluent to a stabilizer column and recovering a stabilizer overhead stream comprising one or more C5⁻

hydrocarbons, a bottom stream comprising at least about 85%, by weight, one or more C6⁺ hydrocarbons, and a side-stream comprising at least about 85%, by weight, one or more C5⁺ hydrocarbons;

C) passing at least a portion of the side-stream to a stripper column; and

D) recycling a stripper bottom stream comprising at least about 90%, by weight, one or more C5⁺ hydrocarbons to a deisopentanizer zone and passing a stream from the deisopentanizer zone to the isomerization reaction zone.

16. The process according to claim 15, wherein the stripper bottom stream upon exiting the stripper column is at a temperature of about 115-about 160°

C.

17. The process according to claim 15, wherein a stripper feed stream is withdrawn from a tray at a top third of the stabilizer column.

18. The process according to claim 15, wherein the deisopentanizer zone further comprises a deisopentanizer column, and the process further comprises withdrawing an overhead stream comprising at least about 85%, by weight, one or more C5 hydrocarbons from the deisopentanizer column.

19. The process according to claim 15, wherein the isomerization reaction zone comprises a catalyst, in turn, comprising a support comprising a sulfated oxide or hydroxide of at least one element of titanium, zirconium, halfnium, and dubnium;

a first component of at least one element of a lanthanide series and yttrium; and

a second component of at least one element of platinum, palladium, ruthenium, rhodium, iridium, and osmium.

20. The process according to claim 15, wherein the isomerization reaction zone comprises a catalyst, in turn, comprising an alumina, a platinum, and a chloride.