Apparatuses and methods for conversion of mercaptans

Patent metadata

Field	Value
Publication number	US-9914886-B2
Application number	US-201414300483-A
Country	US
Kind code	B2
Filing date	Jun 10, 2014
Priority date	Jun 10, 2014
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

Embodiments of apparatuses and methods for conversion of mercaptans are provided. In one example, an apparatus comprises a vessel that is capable to receive a feed stream that comprises liquid hydrocarbons and the mercaptans. The vessel comprises a catalyst bed section that is capable of contacting the feed stream with a catalyst in the presence of oxygen (O 2 ) and caustic at reaction conditions effective to oxidize the mercaptans and form a caustic-containing, sweetened liquid hydrocarbon-containing stream. A coalescing bed section is capable to coalesce and separate at least a portion of the caustic from the caustic-containing, sweetened liquid hydrocarbon-containing stream for forming a caustic-depleted, sweetened liquid hydrocarbon-containing product stream.

First claim

What is claimed is:

1. An apparatus for conversion of mercaptans comprising:
a vessel capable to receive a feed stream that comprises naphtha boiling range hydrocarbons and the mercaptans, wherein the vessel comprises:
a catalyst bed section capable of contacting the feed stream with a catalyst in the presence of oxygen (O 2 ) and caustic at reaction conditions effective to oxidize the mercaptans and form a caustic-containing, sweetened naphtha-containing stream;
a coalescing bed section capable to coalesce and separate at least a portion of the caustic from the caustic-containing, sweetened naphtha-containing stream for forming a caustic-depleted, sweetened naphtha-containing product stream, wherein the coalescing bed section comprises sand;
a coalescing mesh disposed downstream from the coalescing bed section and capable to coalesce and separate an additional portion of the caustic prior to the caustic-depleted, sweetened naphtha-containing product stream being removed from the vessel; and
a liquid permeable support grid supporting the coalescing bed section, the liquid permeable support grid positioned between the coalescing bed section and the coalescing mesh, the liquid permeable support grid allowing the caustic and the caustic-depleted, sweetened naphtha-containing product to flow through the liquid permeable support grid to the coalescing mesh.

2. The apparatus of claim 1 , wherein the catalyst bed section is capable to operate at the reaction conditions that include a temperature of from about 20 to about 65° C.

3. The apparatus of claim 1 , wherein the catalyst bed section is capable to operate at the reaction conditions that include a residence time of from about 15 minutes to about 1 hour.

4. The apparatus of claim 1 , wherein the catalyst bed section is capable to operate at the reaction conditions that include a pressure of from about 345 to about 1030 kPa.

5. The apparatus of claim 1 , wherein the coalescing bed section comprises inert inorganic particulates having an average particle size of from about 0.25 to about 2 mm.

6. The apparatus of claim 1 , wherein the coalescing bed section is capable to operate at conditions that include a residence time of from about 5 to about 15 minutes.

7. The apparatus of claim 1 wherein the coalescing mesh is made of a hydrophilic material or is coated with a hydrophilic material.

8. An apparatus for conversion of mercaptans comprising:
a vessel comprising:
a vessel wall that extends generally vertically and that encloses an internal volume having an upper portion, a lower portion, and an intermediate portion that is disposed between the upper and lower portions, wherein the upper portion of the internal volume is capable to receive a combined stream that comprises naphtha boiling range hydrocarbons, the mercaptans, caustic, and oxygen (O 2 );
a catalyst bed section disposed in the intermediate portion adjacent to the upper portion and capable of contacting the combined stream with a catalyst at reaction conditions effective to oxidize the mercaptans and form a caustic-containing, sweetened naphtha-containing stream;
a coalescing bed section disposed between the catalyst bed section and the lower portion of the internal volume and capable to coalesce and separate at least a portion of the caustic from the caustic-containing, sweetened naphtha-containing stream for forming a caustic-depleted, sweetened naphtha-containing product stream, wherein the coalescing bed section has a thickness of from about 150 to about 300 mm;
a liquid permeable support grid supporting the coalescing bed section, the liquid permeable support grid positioned between the coalescing bed section and a coalescing mesh, the liquid permeable support grid allowing the caustic and the caustic-depleted, sweetened naphtha-containing product to flow through the liquid permeable support grid to the lower portion of the internal volume; and
an outlet having an opening that extends through the vessel wall, wherein the outlet is in fluid communication with the lower portion of the internal volume for removing the caustic-depleted, sweetened naphtha-containing product stream from the vessel.

9. The apparatus of claim 8 , wherein the vessel is capable to operate as a liquid-full vessel.

10. The apparatus of claim 8 , wherein the vessel further comprises a distributor disposed in the upper portion of the internal volume and capable to distribute the combined stream in the upper portion for introduction to the catalyst bed section.

11. The apparatus of claim 10 , further comprising a fluid circuit section in fluid communication with the distributor, wherein the fluid circuit section is capable to receive a feed stream that comprises the naphtha boiling range hydrocarbons and the mercaptans, a caustic stream that comprises the caustic, and an O 2 -containing stream that comprises air to form the combined stream.

12. The apparatus of claim 11 , wherein the fluid circuit section is capable to receive the caustic stream that is an aqueous solution comprising NaOH present in an amount of from about 1 to about 5 wt. % of the aqueous solution.

13. The apparatus of claim 11 , wherein the fluid circuit section is capable to form the combined stream comprising NaOH present in an amount of from about 2 to about 25 ppm.

14. The apparatus of claim 8 , wherein the coalescing bed section comprises the inert inorganic particulates, and wherein the support grid that supports the coalescing bed section is capable to prevent migration of the inert inorganic particulates into the lower portion of the internal volume.

15. The apparatus of claim 8 , wherein the vessel further comprises a baffle section extending from the vessel wall above the opening of the outlet inwardly into the lower portion of the internal volume, wherein the baffle section is capable to obstruct liquid flowing down along the vessel wall in the lower portion of the internal volume from exiting directly through the opening.

16. The apparatus of claim 15 , wherein the baffle section has a distal end portion disposed in the lower portion of the internal volume generally below the opening of the outlet, wherein the coalescing mesh extends between the distal end portion of the baffle section and the vessel wall, and wherein the coalescing mesh is capable to coalesce and separate an additional portion of the caustic prior to advancing the caustic-depleted, sweetened naphtha-containing product stream through the opening of the outlet.

17. The apparatus of claim 8 , wherein the lower portion of the internal volume is capable to allow the at least the portion of the caustic separated from the coalescing bed section to collect to form a spent caustic stream, and wherein the vessel has a spent caustic outlet in fluid communication with the lower portion of the internal volume for removing the spent caustic stream.

18. The apparatus of claim 8 wherein the coalescing mesh is made of a hydrophilic material or is coated with a hydrophilic material.

19. A method for conversion of mercaptans, the method comprising the steps of:
introducing a feed stream that comprises naphtha boiling range hydrocarbons and the mercaptans to a vessel as defined in claim 1 ;
contacting the feed stream with the catalyst in the vessel in the presence of oxygen (O 2 ) and caustic at reaction conditions effective to oxidize the mercaptans and form a caustic-containing, sweetened naphtha-containing stream; and
contacting the caustic-containing, sweetened naphtha-containing stream with inert inorganic particulates t

Assignees

• Uop Llc

Inventors

• Tertel Jonathan Andrew
• Karagic Jasna
• Laricchia Luigi

Classifications

• C10G19/02

  with aqueous alkaline solutions · CPC title

• C10G27/04

  with oxygen or compounds generating oxygen · CPC title

• C10G53/14 Primary

  including at least one oxidation step · CPC title

• B01J8/0242

  the fluid flow within the bed being predominantly vertical · CPC title

• C10G2300/202

  Heteroatoms content, i.e. S, N, O, P · CPC title