Oxidizer and oxidation process for a desulphurization process

• US 7,344,682 B1
• Filed: 03/14/2007
• Issued: 03/18/2008
• Est. Priority Date: 06/05/2006
• Status: Active Grant

• Current Assignee: Merichem Technologies LLC
• Original Assignee: Merichem Company
• Inventors: McManus, Derek, Nagl, Gary J., Reicher, Myron
• Primary Examiner(s): Vanoy; Timothy C.
• Application Number:
  US11/717,908
• Time in Patent Office: 370 Days
• Field of Search: 422/129, 422/168, 422/187, 422/239, 502/38, 502/39
• US Class Current: 422/129
• CPC Class Codes: B01D 53/504 characterised by a specific device
• CPC Class Codes: B01D 53/73 After-treatment of removed components
• CPC Class Codes: B01J 2531/842 Iron
• CPC Class Codes: B01J 31/2243 At least one oxygen and one nitrogen atom present as complexing atoms in an at least bidentate or bridging ligand
• CPC Class Codes: B01J 31/403 containing iron group metals or copper
• CPC Class Codes: B01J 31/4061 involving membrane separation
• CPC Class Codes: B01J 38/12 Treating with free oxygen-containing gas
• CPC Class Codes: C01B 17/05 by wet processes
• CPC Class Codes: Y02P 20/584 Recycling of catalysts

Abstract

An improved oxidizer for liquid reduction-oxidation desulphurization processes uses a hollow fiber membrane contactor. A pressurized, oxygen containing gas stream is introduced into the interior of the hollow fiber membrane while a liquid reduction-oxidation catalyst solution contacts the exterior of the membrane. Oxygen diffuses through the membrane into the liquid reduction-oxidation catalyst solution whereby the solution is oxidized and can be recycled for further us in a desulphurization process.

Claims

1. An oxidizer for liquid redox catalyst solutions comprising, in combination, the following:

a. a housing having first and second ends and a cross-sectional area defining an interior portion;

b. a bundle of hollow fibers having a cross-sectional area and an adjustably supported length within the interior portion of the housing, where each fiber has an internal passage that is accessed through first and second openings;

c. a liquid inlet port located on either the first end of the housing and an outlet port located on the second end of the housing;

d. at least one gas inlet located on either the first or second end of the housing and in fluid communication with either the first or second openings of the bundle of hollow fibers; and

e. a means for adjusting the length of the bundle of hollow fibers.

2. The oxidizer of claim 1 wherein the adjustment means comprises at least one movable plate connected to either the first or second openings of the bundle of hollow fibers and is movably connected to a stationary support fixedly attached to the housing.

3. The oxidizer of claim 2 wherein the movable plate is connected to a screw assembly that is attached to the stationary plate which is fixedly secured to one end of the housing.

4. The oxidizer of claim 1 wherein the cross-sectional area of the housing is at least 2 times the cross-sectional area of the bundle of fibers.

5. The oxidizer of claim 1 wherein a means for preventing channeling of liquid redox solution is positioned within the interior portion of the housing and adjacent to the inlet port.

6. The oxidizer of claim 1 where the oxidizer comprises a membrane comprising a bundle of fibers fabricated from a polymer selected from the group consisting of polypropylene, polyacrylonotrile, polysulfone and polyvinylidine difluoride.

7. A system for oxidizing a liquid reduction-oxidation catalyst solution comprising,

a. a source of pressurized, oxygen containing gas;

b. a hollow fiber membrane oxidizer in fluid communication with the source of pressurized oxygen containing gas; and

c. an absorber vessel in fluid communication with the hollow fiber membrane.

8. The system of claim 7 where the hollow fiber membrane has an interior and an exterior and the pressurized, oxygen containing gas is in fluid communication with the interior of the membrane.

9. The system of claim 7 where the absorber contains a liquid chelated metal catalyst solution.

10. The system of claim 7 where the oxidizer comprises a membrane comprising a bundle of fibers fabricated from a polymer selected from the group consisting of polypropylene, polyacrylonotrile, polysulfone and polyvinylidine difluoride.

11. The system of claim 10 where the membrane is enclosed in more than one vessel in a series flow arrangement.