Water-treatment separating membrane of high flux having good chlorine resistance

Patent metadata

Field	Value
Publication number	US-9259691-B2
Application number	US-201414264864-A
Country	US
Kind code	B2
Filing date	Apr 29, 2014
Priority date	Nov 21, 2012
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A water-treatment separating membrane includes a polyamide active layer formed on a porous support. When the polyamide active layer is dyed using a 5% aqueous solution of Rhodamine B, at least a curve pattern formed by connecting two or more arcs is formed in at least a partial area of the polyamide active layer.

First claim

What is claimed is:

1. A water-treatment separating membrane comprising:
a polyamide active layer formed on a porous support;
wherein the polyamide active layer is formed by dropping droplets of an organic solution including an acyl halide compound on an aqueous amine solution layer and includes a center portion in which a degree of an interfacial polymerization of the organic solution is high and a critical area in which the degree of the interfacial polymerization of the organic solution is low,
wherein the volume of the organic solution per droplet is from 0.001 ml to 5 ml,
wherein at least a curve pattern formed by connecting two or more arcs is formed in at least a partial area of the polyamide active layer, and the curve pattern can be made visible when the polyamide active layer is dyed using a 5% aqueous solution of Rhodamine B,
wherein at least one of the two or more arcs is a portion of a closed circular curve,
wherein a major diameter of the closed circular curve is from 5 mm to 100 mm, and
wherein an arithmetic mean roughness (Ra) of a surface of the polyamide active layer is from 60 nm to 100 nm.

2. The water-treatment separating membrane of claim 1 , wherein the curve pattern has a form obtained by connecting both end points of each arc with respective curve portions of other arcs.

3. The water-treatment separating membrane of claim 1 , wherein the curve pattern has a form obtained by arranging the two or more arcs in a row, and connecting end points of the arcs to connect adjacent arcs.

4. The water-treatment separating membrane of claim 2 , wherein the two or more arcs are arranged convexly in the same direction.

5. The water-treatment separating membrane of claim 3 , wherein the curve patterns are repeatedly formed in a direction perpendicular with respect to an arranging direction of the two or more arcs.

6. The water-treatment separating membrane of claim 1 , wherein the closed circular curve is provided in plural and arranged irregularly or regularly.

7. The water-treatment separating membrane of claim 1 , wherein a distance between centers of the circular closed curves is from 1 mm to 50 mm.

8. The water-treatment separating membrane of claim 1 , wherein a thickness of the curve pattern is from 4% to 25% of a major diameter of the circular closed curve.

9. The water-treatment separating membrane of claim 1 , wherein the curve pattern is formed in a critical area in which a degree of polyamide polymerization is low.

10. A water-treatment module comprising at least one water-treatment separating membrane of claim 1 .

11. A water-treatment apparatus comprising at least one water-treatment module of claim 10 .

12. The water-treatment separating membrane of claim 3 , wherein the two or more arcs are arranged convexly in the same direction.

Assignees

• Lg Chemical Ltd

Inventors

• Ko Young-Hoon
• Kim Jae-Hong
• Shin Chong-Kyu
• Lee Phill

Classifications

• B01D2325/30

  Chemical resistance · CPC title

• B01D67/0006

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

• B01D71/82 Primary

  characterised by the presence of specified groups, e.g. introduced by chemical after-treatment · CPC title

• B01D67/0088

  Physical treatment with compounds, e.g. swelling, coating or impregnation · CPC title

• B01D69/02 Primary

  characterised by their properties · CPC title