Purification of mercaptans or thiophenes using dividing wall column distillation

Patent metadata

Field	Value
Publication number	US-10807949-B2
Application number	US-201716315689-A
Country	US
Kind code	B2
Filing date	Jan 19, 2017
Priority date	Jan 22, 2016
Publication date	Oct 20, 2020
Grant date	Oct 20, 2020

Abstract

Aspects of the present invention relate to systems and processes for obtaining desired mercaptans or thiophenes from a feed stream containing a mixture of mercaptans, thiophenes and other components. In one aspect of the invention, a system for separating one or more components from a feed stream of mixed mercaptans includes one or more distillation columns in connection with a feed containing mercaptans, the distillation column having a rectification section, a stripping section, and a feed side section separated from a side draw section by a dividing wall that extends from the rectification section to the stripping section. The distillation column further being in connection with a condenser and a reboiler; and a distillate stream, a side drawn stream, and a bottoms stream.

First claim

What is claimed is:

1. A process for separating as a side draw stream a primary mercaptan of 4-16 carbon chain length and optionally thiopene from a feed stream, said feed stream containing a mixture comprising primary, secondary and tertiary mercaptans using a distillation column, the process comprising:
providing one or more distillation columns with said feed stream, the distillation column having a rectification section, a stripping section, and a feed side section separated from a side draw section by a dividing wall that extends from the rectification section to the stripping section;
condensing a vapor from the distillation column with a condenser and heating a liquid from the distillation column with a reboiler;
removing a distillate stream from a top region of the distillation column;
removing said side draw stream of a primary mercaptan of 4-16 carbon chain length from a side region of the distillation column; and
removing a bottoms stream from a bottom region of the distillation column.

2. The process of claim 1 , wherein one or two distillation columns are utilized.

3. The process of claim 1 , wherein one distillation column is utilized.

4. The process of claim 1 , wherein compounds sent to the bottoms stream only pass through one reboiler.

5. The process of claim 1 , wherein the feed side section comprises less than 40% of the column cross sectional area.

6. The process of claim 1 , wherein more than 90% of the mercaptans pass one or fewer times through one or more reboilers.

7. The process of claim 6 , wherein the distillate stream and the side draw stream together contain the majority of mercaptans from the feed stream.

8. The process of claim 1 , wherein the reboiler is operated at a temperature of 240 degrees Celsius or less.

9. The process of claim 1 , wherein the condenser utilizes a coolant, and the coolant is selected from the group consisting of cooling air and cooling water.

10. The process of claim 1 , wherein a liquid coming from the rectification section is controllably distributed to the feed side section and the side draw section of the distillation column.

11. The process of claim 10 , wherein less than 10% by volume of the liquid coming from the rectification section enters the feed side section.

12. The process of claim 1 , wherein a height of the dividing wall is between 35% and 80% of a height of the distillation column.

13. The process of claim 1 , wherein the dividing wall extends more than 45% and less than 80% of one or more theoretical stages of the distillation column.

14. The process of claim 1 , wherein the dividing wall extends more than 55% and less than 70% of the theoretical stages of the distillation column.

15. The process of claim 1 , wherein the dividing wall extends more than 60% and less than two thirds of the theoretical stages of the distillation column.

Assignees

• Arkema Inc

Inventors

• Schon Steven G
• Aguiar Rose
• Amstutz Jerome
• Caumia Sylvie
• Goddard Andrew R
• Shah Shashank N
• Smith Gary S

Classifications

• C07C319/28 Primary

  Separation; Purification · CPC title

• C07C319/30

  from the by-products of refining mineral oils · CPC title

• C10G29/28

  containing sulfur as the only hetero atom, e.g. mercaptans, or sulfur and oxygen as the only hetero atoms · CPC title

• B01D3/32 Primary

  Other features of fractionating columns {; Constructional details of fractionating columns not provided for in groups B01D3/16 - B01D3/30} · CPC title

• B01D3/4216

  Head stream · CPC title