Coated porous filter membranes and related methods

Patent metadata

Field	Value
Publication number	US-2025099918-A1
Application number	US-202418891895-A
Country	US
Kind code	A1
Filing date	Sep 20, 2024
Priority date	Sep 22, 2023
Publication date	Mar 27, 2025
Grant date	—

Abstract

Described are coated porous polymeric filter membranes that include a filter membrane substrate and an ionic polymer coating applied to the surface of the substrate; methods of making the coated porous polymeric filter membranes and filters that include such a coated membrane; and method of using the coated membranes to remove metal ions from purified water.

First claim

1 . A coated porous polymeric membrane comprising:
(i) a porous polymeric membrane substrate exhibiting:
(a) a substrate flow time measured as deionized water flow time, and
(b) a bubble point in a range from 2 to 200 pounds per square inch measured using ethoxy-nonafluorobutane; and
(ii) an ionic polymer coating at a surface of the porous polymeric membrane substrate, the ionic polymer coating comprising monomeric units derived from an ionic monomer and a crosslinker monomer; wherein the coated porous polymeric membrane exhibits a coated membrane flow time measured as deionized water flow time, the coated membrane flow time being no more than 50% greater than the substrate flow time of the porous polymeric membrane substrate when it does not have the ionic polymer coating.

2 . The coated porous polymeric membrane of claim 1 , wherein
the porous polymeric membrane substrate has a bubble point greater than 140 pounds per square inch, and the coated membrane flow time is no more than 50% greater than the substrate flow time of the porous polymeric membrane substrate when it does not have the ionic polymer coating.

3 . The coated porous polymeric membrane of claim 1 , wherein
the porous polymeric membrane substrate has a bubble point between 80 pounds per square inch and 140 pounds per square inch, and the coated porous polymeric membrane flow time is not more than 40% greater than the substrate flow time of the porous polymeric membrane substrate when it does not have the ionic polymer coating.

4 . The coated porous polymeric membrane of claim 1 , wherein
the porous polymeric membrane substrate has a bubble point below 80 pounds per square inch, and the coated porous polymeric membrane flow time is not more than 30% greater than the flow time of the uncoated membrane substrate.

5 . The coated porous polymeric membrane of claim 1 wherein the crosslinker monomer comprises a di-ethylenically-unsaturated monomer.

6 . The coated porous polymeric membrane of claim 5 , wherein the di-ethylenically-unsaturated monomer comprises a di-ethylenically-unsaturated cationic monomer, a di-ethylenically-unsaturated anionic monomer, a di-ethylenically-unsaturated zwitterionic monomer, or any combination thereof.

7 . The coated porous polymeric membrane of claim 1 , wherein the porous polymeric membrane substrate comprises polyphenylsulfone and the coated porous polymeric membrane has a dye binding capacity of greater than 5 micrograms per square centimeter.

8 . The coated porous polymeric membrane of claim 1 , wherein the porous polymeric membrane substrate comprises polytetrafluoroethylene and the coated porous polymeric membrane has a dye binding capacity of greater than 50 micrograms per square centimeter.

9 . The coated porous polymeric membrane of claim 1 , wherein the porous polymeric membrane substrate comprises polyphenylsulfone and the coated porous polymeric membrane has a deionized water flow time of less than 400 seconds.

10 . The coated porous polymeric membrane of claim 1 , wherein the porous polymeric membrane substrate comprises polytetrafluoroethylene and the coated porous polymeric membrane has a deionized water flow time of less than 400 seconds.

11 . The coated porous polymeric membrane of claim 1 , wherein the coated porous polymeric membrane is characterized as removing, from purified water, at least 40 percent of one or more of the following metal ions: vanadium, iron, molybdenum, tin, tantalum, and tungsten.

12 . The coated porous polymeric membrane of claim 1 , wherein the coated porous polymeric membrane is characterized as removing, from purified water, at least 60 percent of one or more of the following metal ions: molybdenum, tin, tantalum, and tungsten.

13 . A method of removing metal ions from purified water, the method comprising:
flowing purified water that contains metal ions through the coated membrane of claim 1 thereby removing metal ions from the purified water.

14 . The method of claim 13 , comprising removing from the purified water at least 40 percent of one or more of the following metal ions: vanadium, iron, molybdenum, tin, tantalum, and tungsten.

15 . The method of claim 13 , comprising removing from the purified water at least 60 percent of one or more of the following metal ions: molybdenum, tin, tantalum, and tungsten.

Assignees

• Entegris Inc

Inventors

• Gjoka Alketa
• Jaber Jad Ali
• Ngan Clifton G
• Hamzik James
• Crespo David
• Ly Saksatha
• Webb Christopher W
• Thomas Jikku
• Kamimoto Satoshi
• Batra Gaurav M
• Sampath Siddarth

Classifications

• B01D61/14

  Ultrafiltration; Microfiltration · CPC title

• B01D2323/36

  Introduction of specific chemical groups · CPC title

• B01D2323/40

  in-situ membrane formation · CPC title

• B01D69/1251

  by interfacial polymerisation · CPC title

• B01D67/0006

  by chemical reactions (in-situ polymerisation, polycondensation, cross-linking or reaction for manufacturing composite membranes B01D69/125) · CPC title