Method of preparing or reconditioning a leak stable gas separation membrane system

Patent metadata

Field	Value
Publication number	US-9533263-B2
Application number	US-201514703086-A
Country	US
Kind code	B2
Filing date	May 4, 2015
Priority date	Nov 16, 2011
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A method of making a gas separation membrane by providing a plating vessel with a volume of plating solution of gas-selective metal ions into which is placed a porous support. The plating solution is circulated over a surface of the porous support while maintaining conditions within the plating vessel so as to promote the electroless deposition. The circulation rate of the plating solution is such as to enhance the metal deposition onto the surface of the porous support in the formation of the gas separation membrane.

First claim

What is claimed is:

1. A method of making a gas separation membrane, wherein said method comprises:
(a) providing a plating vessel containing a volume of a plating solution having a concentration of a gas-selective metal ion;
(b) placing a porous support, having a first surface and a second surface with each said surface being opposed to the other to thereby define a support thickness, into said plating solution and thereby contacting said first surface with said plating solution for a time period while maintaining plating conditions within said plating vessel so as to promote the electroless deposition of said gas-selective metal ion from said plating solution onto said first surface of said porous support so as to thereby create a concentration profile of said gas-selective metal ion within said plating solution extending from said first surface to a distance point away from said first surface at which the derivative of said concentration profile approaches zero;
(c) circulating said plating solution through said plating vessel at a circulation rate in the range of from 0.1 minutes to 180 minutes (plating vessel volume per plating solution volumetric flow per minutes) so as to reduce said distance point; whereby a membrane layer of said gas selective metal is deposited upon said first surface to thereby provide a supported membrane;
(d) after said time period, removing said supported membrane from said plating solution and annealing said supported membrane to provide an annealed supported membrane having an annealed membrane layer;
(e) placing said annealed supported membrane into a second plating solution, having a second gas-selective metal ion concentration, contained within said plating vessel or a second plating vessel and thereby contacting said annealed membrane layer with said second plating solution for a second time period while maintaining plating conditions within said plating vessel or said second plating vessel and while causing a second concentration profile of said second gas-selective metal ion to form within said second plating solution, said concentration profile extending from said annealed membrane layer to a second distance point away from said annealed membrane layer at which the derivative of said second concentration profile approaches zero;
(f) measuring the density of said annealed membrane layer to determine its density to liquid, and if said annealed membrane layer is determined to be liquid dense, then applying during the contacting of said annealed, membrane layer with said second plating solution a pressure differential of a higher pressure and a lower pressure across said support thickness with said higher pressure being applied to the side of said first surface; and
(g) circulating said second plating solution through said plating vessel or second platting vessel at a second circulation rate such that said second distance point is significantly reduced;
whereby a second membrane layer of said second gas-selective metal is deposited upon said annealed membrane layer to thereby provide a second supported membrane.

2. A method as recited in claim 1 , further comprising: repeating steps (d), (e), (f) and (g) with each resulting supported membrane and each resulting annealed membrane layer until the resulting annealed membrane layer is gas dense.

3. A method as recited in claim 2 , wherein said circulation rate is such as to provide for a residence time of said plating solution through said plating vessel that is in the range of from 0.1 minutes to 30 minutes.

4. A method as recited in claim 1 wherein said step of applying a pressure differential is accomplished, at least in part, by applying a vacuum to said second surface of said porous support.

5. A method as recited in claim 1 wherein said step of applying a pressure differential is accomplished, at least in part, by increasing the pressure applied to said first surface of said porous support as compared to the pressure applied to said second surface of said porous support.

6. A method as recited in claim 1 wherein there is a pre-existing layer of gas-selective metal on said first surface of said porous support.

7. A method as recited in claim 1 wherein the gas-selective metal is selected from the group consisting of palladium, gold, and alloys thereof.

8. A method of making a gas separation membrane, wherein said method comprises:
(a) providing a plating vessel containing a volume of a plating solution having a concentration of a pas-selective metal ion;
(b) placing a porous support, having a first surface and a second surface with each said surface being opposed to the other to thereby define a support thickness, into said plating solution and thereby contacting said first surface with said plating solution for a time period while maintaining plating conditions within said plating vessel so as to promote the electroless deposition of said gas-selective metal ion from said plating solution onto said first surface of said porous support;
(c) circulating said plating solution through said plating vessel at a circulation rate such as to provide for a residence time of said plating solution through said plating vessel that is in the range of from 0.1 minutes to 30 minutes; whereby a membrane layer of said gas-selective metal is deposited upon said first surface to thereby provide a supported membrane;
(d) after said time period, removing said supported membrane from said plating solution and annealing said supported membrane to provide an annealed supported membrane having an annealed membrane layer;
(e) placing said annealed supported membrane into a second plating solution, having a second gas-selective metal ion concentration, contained within said plating vessel or a second plating vessel and thereby contacting said annealed membrane layer with said second plating solution for a second time period while maintaining plating conditions within said plating vessel or said second plating vessel;
(f) measuring the density of said annealed membrane layer to determine its density to liquid, and if said annealed membrane layer is determined to be liquid dense, then applying during the contacting of said annealed membrane layer with said second plating solution a pressure differential of a higher pressure and a lower pressure across said support thickness with said higher pressure being applied to the side of said first surface; and
(g) circulating said second plating solution through said plating vessel or second plating vessel at a second circulation rate such as to provide for a residence time of said second plating solution through said plating vessel or second plating vessel that is in the range of from 0.1 minutes to 30 minutes;
whereby a second membrane layer of said second gas-selective metal is deposited upon said annealed membrane layer to thereby provide a second supported membrane.

9. A method as recited in claim 8 , further comprising;
repeating steps (d), (e), (f) and (g) with each resulting supporting membrane and each resulting annealed membrane layer until the resulting annealed membrane layer is gas dense.

10. A method as recited in claim 8 wherein said step of applying a pressure differential is accomplished, at least in part, by applying a vacuum to said second surface of said porous support.

11. A method as recited in claim 8 wherein said step of applying a pressure differential is accomplished, at least in part, by increasing the pressure applied to said first surface of said porous support as compared to the pressure applied to said second surface of said porous support.

12. A method as recited in claim 8 wherein there is a pre-existing layer of gas-selective metal on

Assignees

• Shell Oil Co

Inventors

• Saukaitis John Charles

Classifications

• C01B3/505

  Membranes containing palladium · CPC title

• B01D53/228

  characterised by specific membranes · CPC title

• B01D2323/42

  Details of membrane preparation apparatus · CPC title

• B01D2323/46

  Impregnation · CPC title

• B01D46/0001

  Making filtering elements · CPC title