Process for increasing the yield of an isomerization zone fractionation

Patent metadata

Field	Value
Publication number	US-9302956-B2
Application number	US-201414267737-A
Country	US
Kind code	B2
Filing date	May 1, 2014
Priority date	May 1, 2014
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A process for increasing a yield of an isomerization zone by removing at least a portion of the C 6 cyclic hydrocarbons from a stream prior to it being passed into the isomerization zone. Additionally, disproportionation reactions occur producing valuable C 3 hydrocarbons and C 4 hydrocarbons. Also, a higher ring opening conversion of C 5 cyclic hydrocarbons is observed.

First claim

What is claimed is:

1. A process for increasing the yield of normal paraffins in an isomerization zone, the process comprising:
separating a portion of C6 cyclic hydrocarbons from a naphtha stream comprising C5+ hydrocarbons to provide a C6 cyclic hydrocarbons lean stream;
separating iC5 paraffinic hydrocarbons and iC6 paraffinic hydrocarbons from the C6 cyclic hydrocarbons lean stream;
passing a feed stream comprising at least one stream being rich in iC5 paraffinic hydrocarbons, iC6 paraffinic hydrocarbons to an isomerization zone containing a chlorided alumina catalyst to disproportionate at least two iC5 and/or iC6 paraffinic hydrocarbons to produce iC4 paraffinic hydrocarbons, and isomerize the produced iC4 paraffinic hydrocarbons, iC5 and iC6 isoparaffins to normal paraffins;
converting the C6 cyclic hydrocarbons to straight chain hydrocarbons in a ring opening reactor;
separating a reactor effluent from the ring opening reactor into a plurality of streams, at least one stream from the plurality of streams comprising n-pentane, iC5 hydrocarbons, n-hexane, and iC6 hydrocarbons; and,
combining the at least one stream from the plurality of streams comprising n-pentane, iC5 hydrocarbons, n-hexane, and iC6 hydrocarbons with the C6 cyclic hydrocarbons lean stream.

2. The process of claim 1 further comprising:
separating an effluent from the isomerization zone into an overhead stream comprising C 4 − hydrocarbons and a bottoms stream comprising C 5 + hydrocarbons.

3. The process of claim 2 further comprising:
combining the bottoms stream comprising C 5 + hydrocarbons with at least a portion of the naphtha stream.

4. The process of claim 1 further comprising:
passing the naphtha stream to a first separation zone; and,
separating the naphtha stream in the first separation zone into an overhead stream and a bottoms stream, the overhead stream being the C 6 cyclic hydrocarbons lean stream and the bottoms stream being rich in n-hexane and C 6 cyclic hydrocarbons.

5. The process of claim 4 further comprising:
passing the overhead stream from the first separation zone to a second separation zone; and,
separating the overhead stream from the first separation zone in the second separation zone into the at least one stream being rich in iC 5 isoparaffinic hydrocarbons, iC 6 isoparaffinic hydrocarbons, or both.

6. The process of claim 5 wherein the second separation zone comprises:
at least two separator columns.

7. The process of claim 5 further comprising:
separating the overhead stream from the first separation zone in a first separator column of the second separation zone into an overhead stream, an intermediate stream, a bottoms stream,
the overhead stream from the first separator column of the second separation zone being rich in C 5 hydrocarbons, and,
the intermediate stream of the first separator column of the second separation zone being rich in iC 6 isoparaffinic hydrocarbons.

8. The process of claim 7 , further comprising:
separating the overhead stream from the first separator column of the second separation zone in a second separator column of the second separation zone into an overhead stream and a bottoms stream,
the overhead stream of the second separator column of the second separation zone being rich in iC 5 isoparaffinic hydrocarbons.

9. The process of claim 8 further comprising:
recycling the bottoms stream from the isomerization zone to the first column from the second separation zone.

10. The process of claim 8 further comprising:
combining the bottoms stream from the first separator column and the second separator column.

11. The process of claim 9 wherein the second separation zone comprises:
at least one adsorption zone.

12. The process of claim 11 further comprising:
separating the overheads stream from the first separation zone in the at least one absorption zone into a first stream and a second stream,
the first stream being rich in iC 5 isoparaffinic hydrocarbons and iC 6 isoparaffinic hydrocarbons and,
the second stream being rich in at least n-pentane.

13. The process of claim 12 further comprising:
recycling the bottoms stream from the isomerization zone to the first separation zone.

Assignees

• Uop Llc

Inventors

• Lapinski Mark P
• Lippmann Matthew
• Funk Gregory
• Shecterle David James
• Mokka Lakshmi P

Classifications

• C07C5/00

  Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms · CPC title

• C07C5/27

  Rearrangement of carbon atoms in the hydrocarbon skeleton · CPC title

• C07C7/005 Primary

  Processes comprising at least two steps in series · CPC title

• C07C4/06 Primary

  Catalytic processes {(C07C4/025 takes precedence)} · CPC title

• C07C2523/42

  Platinum · CPC title