Polyamide-based water-treatment separation membrane having excellent durability, and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-10112154-B2
Application number	US-201414908973-A
Country	US
Kind code	B2
Filing date	Aug 1, 2014
Priority date	Aug 1, 2013
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

The present invention relates to a water treatment separation membrane having improved durability and including a porous support; a polyamide active layer formed on the porous support; and a protective layer formed on the polyamide active layer and including polyvinyl pyrrolidone, wherein a thickness of the protective layer is 0.5 nm to 1000 nm, and a method for manufacturing the same.

First claim

The invention claimed is:

1. A water treatment separation membrane comprising:
a porous support;
a polyamide active layer formed on the porous support; and
a protective layer formed on the polyamide active layer, the protective layer comprising
polyvinyl pyrrolidone and a polymer including an amine group-containing compound, an epoxy group-containing compound and a fluoro-containing compound,
wherein a thickness of the protective layer is 0.5 nm to 1000 nm.

2. The water treatment separation membrane of claim 1 , wherein the polyvinyl pyrrolidone has a weight average molecular weight of 10,000 to 1,000,000.

3. The water treatment separation membrane of claim 1 , wherein the polyvinyl pyrrolidone has a solubility value of 5% or greater in water at 25° C.

4. The water treatment separation membrane of claim 1 , wherein the protective layer includes a first protective layer including the polymer that includes the amine group-containing compound, the epoxy group-containing compound and the fluoro-containing compound; and
a second protective layer formed on the top of the first protective layer and including polyvinyl pyrrolidone.

5. The water treatment separation membrane of claim 1 , wherein the amine group-containing compound is a compound in which amine groups are attached to both ends of polyalkylene glycol.

6. The water treatment separation membrane of claim 1 , wherein the amine group-containing compound is a compound of Chemical Formula 2:

wherein, in Chemical Formula 2, m is an integer of 0 to 10, n is an integer of 0 to 15, and o is an integer of 0 to 10.

7. The water treatment separation membrane of claim 1 , wherein the epoxy group-containing compound includes one or more types selected from the group consisting of a (poly)ethylene-based epoxy resin, a (poly)glycerin-based epoxy resin and a (poly)sorbitol-based epoxy resin, which include two or more epoxy groups.

8. The water treatment separation membrane of claim 1 , wherein the epoxy group-containing compound is a compound of Chemical Formula 3:

wherein, in Chemical Formula 3:
R 1 is hydrogen or a hydroxyl group;
R 2 to R 5 are each independently hydrogen, a hydroxyl group or an alkoxyalkyl oxirane group;
a is an integer of 0 to 150;
b is an integer of 0 to 3; and
c is an integer of 0 to 5.

9. The water treatment separation membrane of claim 1 , wherein the amine group-containing compound and the epoxy group-containing compound are included in a weight ratio of 10:1 to 1:1.

10. The water treatment separation membrane of claim 1 , wherein the fluoro-containing compound includes one or more types selected from the group consisting of F(CF 2 ) 3 O[CF(CF 3 )CF 2 O] 3 CF(CF 3 )COF, CHF 2 CF 2 CF 2 CH 2 OCH 2 CHCH 2 O, CHF 2 CF 2 CF 2 CF 2 CH 2 OCH 2 CHCH 2 O, F(CH 2 ) 10 COOH, F(CH 2 ) 7 COCl, F(CH 2 ) 10 CH 2 CH 2 OH, F(CH 2 ) 8 CH 2 CH 2 OH, (CF 3 ) 2 CCH 3 COF, F(CF 2 ) 6 CH 2 CHCH 2 O, CF 3 CHCHCOC, and F(CF 2 ) 6 CH 2 NH 2 .

11. The water treatment separation membrane of claim 1 , wherein the polymer including the amine group-containing compound, the epoxy group-containing compound and the fluoro-containing compound includes at least one or more compounds of Chemical Formulae 7 and 8:

wherein, in Chemical Formulae 7 and 8:
A is a fluoro group-substituted C 1-20 alkylene group, an aryl alkylene group, an alkylene oxide group, an alkenylene group, an aryl alkenylene group or an alkenylene oxide group;

R 1 is hydrogen or a hydroxyl group;
R 2 to R 5 are each independently hydrogen, a hydroxyl group or an alkoxyalkyl oxirane group;
a is an integer of 0 to 150;
b is an integer of 0 to 3;
c is an integer of 0 to 5;
m is an integer of 0 to 10;
n is an integer of 0 to 15; and
o is an integer of 0 to 10.

12. The water treatment separation membrane of claim 11 , wherein the A is F(CF 2 ) 3 O[CF(CF 3 )CF 2 O] 3 CF(CF 3 )CO—, CHF 2 CF 2 CF 2 CH 2 OCH 2 CHOHCH 2 —, CHF 2 CF 2 CF 2 CF 2 CH 2 OCH 2 CHOHCH 2 —, F(CH 2 ) 10 CO—, F(CH 2 ) 7 CO—, F(CH 2 ) 10 CH 2 CH 2 O—, F(CH 2 ) 8 CH 2 CH 2 O—, (CF 3 ) 2 CCH 3 CO—, F(CF 2 ) 6 CH 2 CHOHCH 2 —, CF 3 CHCHCO— or F(CF 2 ) 6 CH 2 NH—.

13. The water treatment separation membrane of claim 1 , which has a moisture content of 1% to 8%.

14. The water treatment separation membrane of claim 1 , which has salt rejection of 99.3% or greater, and permeate flow of 30 to 45 gallon/ft 2 ·day or greater in a dried state.

15. The water treatment separation membrane of claim 1 , which has a permeate flow change ratio of 10% or less after passing through an aqueous solution mixed with an aqueous sodium chloride solution having a concentration of 32,000 ppm, and albumin having a concentration of 100 ppm for 6 hours, compared to initial permeate flow.

16. A water treatment module comprising at least one or more of the water treatment separation membranes of claim 1 .

17. A method for manufacturing a water treatment separation membrane comprising:
forming a polyamide active layer on a porous support; and
forming a protective layer on the polyamide active layer by:
a) mixing a polymer including an amine group-containing compound, an epoxy group-containing compound and a fluoro-containing compound with an aqueous solution including 0.005% by weight to 7% by weight of polyvinyl pyrrolidone based on the whole aqueous solution to form a mixed aqueous solution, and coating the mixed aqueous solution on the polyamide active layer.

Assignees

• Lg Chemical Ltd

Inventors

• Lee Youngju
• Shin Chong Kyu
• Lee Phill
• Jeon Byungho

Classifications

• B01D2325/04

  Characteristic thickness · CPC title

• B01D2325/28

  Degradation or stability over time · CPC title

• B01D71/56 Primary

  Polyamides, e.g. polyester-amides · CPC title

• B01D69/02

  characterised by their properties · CPC title

• B01D71/28

  Polymers of vinyl aromatic compounds · CPC title