Composite nanoporous metal membrane

Patent metadata

Field	Value
Publication number	US-12290786-B2
Application number	US-202318367969-A
Country	US
Kind code	B2
Filing date	Sep 13, 2023
Priority date	Dec 14, 2018
Publication date	May 6, 2025
Grant date	May 6, 2025

Abstract

A composite nanoporous metal membrane, a method of making same, and a method of using same to filter supercritical CO 2 are provided. The method of making generally includes a) providing a sintered coarse porous layer; b) applying to an outer face of the coarse porous layer second metal particles; c) sintering to form a structure comprising coarse and intermediate layers; d) applying a suspension of third metal particles; e) drying the suspension of third particles; f) pressing the dried layer of third particles; and g) sintering to form a composite nanoporous metal membrane. The composite nanoporous metal membrane generally includes: a) a sintered coarse layer; b) an intermediate layer comprising first metal particles and second metal particles joined in a sintered structure which is sintered to the coarse layer; and c) a fine layer comprising third metal particles joined in a sintered structure which is sintered to the intermediate layer.

First claim

I claim:

1. A method of making a composite nanoporous metal membrane comprising:
a) providing a coarse porous layer comprising first particles comprising a first metal or alloy in metallic state, the first particles having an average diameter of 50-200 micrometers and a first sintering temperature, wherein the first particles of the coarse layer are joined in a sintered structure;
b) applying, to an outer face of the coarse porous layer, second particles comprising a second metal or alloy in metallic state to form a first intermediate structure, the second particles having an average diameter of 1-5 micrometers and a second sintering temperature;
c) sintering the first intermediate structure at a temperature less than the first sintering temperature to form a second intermediate structure comprising coarse and intermediate layers;
d) applying to the second intermediate structure a suspension of third particles comprising a third metal or alloy in metallic state, the third particles having an average diameter of 50-150 nanometers and a third sintering temperature;
e) drying the suspension of third particles to form a third particle layer borne on the second intermediate structure;
f) pressing the third particle layer borne on the second intermediate structure together with the second intermediate structure to form a third intermediate structure; and
g) sintering the third intermediate structure at a temperature less than the second sintering temperature to form a composite nanoporous metal membrane.

2. The method according to claim 1 , wherein the second particles having an average diameter of 1-4 micrometers.

3. The method according to claim 1 , wherein step f) comprises uniform orthogonal compression of the third particle layer.

4. The method according to claim 1 , wherein the suspension of third particles is a suspension in a solvent system of one or more alcohols and/or water.

5. The method according to claim 1 , wherein the suspension of third particles is a suspension in a solvent system having a surface tension of less than 30.0 millinewtons per meter at 20° C.

6. The method according to claim 1 , wherein the composite nanoporous metal membrane has a bubble point of 207 kPa (30 PSI) or greater as measured by an IPA Bubble Point Test Method and an air permeability of 0.200 slpm/cm 2 or greater as measured by an Air Permeability Test Method.

7. The method according to claim 1 , wherein the composite nanoporous metal membrane has a bubble point of 380 kPa (55 PSI) or greater as measured by an IPA Bubble Point Test Method.

8. The method according to claim 1 , wherein the composite nanoporous metal membrane comprises pores capable of passing liquids or supercritical fluids.

9. The method according to claim 1 , wherein the first, second, and third metals are independently selected from the group consisting of stainless steel and nickel.

Assignees

• Entegris Inc

Inventors

• Zeller Robert

Classifications

• B01D2325/0283

  Pore size · CPC title

• B01D71/02232

  Nickel · CPC title

• B01D69/1216

  Three or more layers · CPC title

• B01D2257/504

  Carbon dioxide · CPC title

• B01D2325/20

  Specific permeability or cut-off range · CPC title