US 12,290,786 B2
Composite nanoporous metal membrane
Robert Zeller, Boston, MA (US)
Assigned to ENTEGRIS, INC., Billerica, MA (US)
Filed by ENTEGRIS, INC., Billerica, MA (US)
Filed on Sep. 13, 2023, as Appl. No. 18/367,969.
Application 18/367,969 is a division of application No. 16/691,226, filed on Nov. 21, 2019, abandoned.
Claims priority of provisional application 62/779,610, filed on Dec. 14, 2018.
Prior Publication US 2024/0001307 A1, Jan. 4, 2024
Int. Cl. B01D 67/00 (2006.01); B01D 69/12 (2006.01); B01D 71/02 (2006.01)
CPC B01D 67/00411 (2022.08) [B01D 67/0069 (2013.01); B01D 69/1216 (2022.08); B01D 71/02232 (2022.08); B01D 2257/504 (2013.01); B01D 2325/0283 (2022.08); B01D 2325/20 (2013.01)] 9 Claims
OG exemplary drawing
 
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.