Multilayer separation membrane

Patent metadata

Field	Value
Publication number	US-2016310907-A1
Application number	US-201415103591-A
Country	US
Kind code	A1
Filing date	Nov 27, 2014
Priority date	Dec 13, 2013
Publication date	Oct 27, 2016
Grant date	—

Abstract

An object of the present invention is to provide a multilayer separation membrane having excellent performance on both removal of suspended solids in water and adsorptive removal of metal ions in water. A multilayer separation membrane of the present invention includes: a porous adsorption layer including substantially a polymer having chelating functional groups; and a porous clarification layer and the porous clarification layer is disposed neater to a raw water-side than the porous adsorption layer.

First claim

1 . A multilayer separation membrane comprising:
a porous adsorption layer comprising substantially a polymer having chelating functional groups; and a porous clarification layer disposed nearer to a raw water-side than the porous adsorption layer.

2 . The multilayer separation membrane according to claim 1 , wherein an average pore diameter A of pores in the porous adsorption layer and an average pore diameter B at a surface of the porous clarification layer satisfy a relation A>B.

3 . The multilayer separation membrane according to claim 1 , wherein the porous adsorption layer has a thickness of 10 μm to 500 μm.

4 . The multilayer separation membrane according to claim 1 , wherein the porous adsorption layer is a layer throughout which the polymer having the chelating functional groups is distributed uniformly, and
when elemental analysis on cross sections of the porous adsorption layer is performed by an energy-dispersive X-ray analysis, an average value X of atom counts (%) of atoms derived from the chelating functional groups and a standard deviation Y thereof satisfy a relation X≧3Y.

5 . The multilayer separation membrane according to claim 4 , wherein the atoms derived from the chelating functional groups are at least one selected from the group consisting of N, O, P, S, Na and K.

6 . The multilayer separation membrane according to claim 1 , further comprising a supporting layer.

7 . The multilayer separation membrane according to claim 1 , which has a pure-water permeability of 0.10 m 3 /m 2 /hr to 10 m 3 /m 2 /hr under 50 kPa at 25° C., a rupture strength of 6 MPa or higher, and a rupture elongation of 10% or higher.

8 . The multilayer separation membrane according to claim 1 , wherein the porous adsorption layer is a layer obtained in accordance with a thermally-induced phase separation method and/or a nonsolvent-induced phase separation method.

9 . The multilayer separation membrane according to claim 1 , wherein the porous clarification layer is a layer obtained in accordance with a thermally-induced phase separation method and/or a nonsolvent-induced phase separation method.

Assignees

• Toray Industries

Inventors

• Hanakawa Masayuki
• Takada Koichi
• Tokuyama Takahiro
• Iwai Kenta

Classifications

• B01J20/3293

  Coatings on a core, the core being particle or fiber shaped, e.g. encapsulated particles, coated fibers · CPC title

• C02F1/285

  using synthetic organic sorbents · CPC title

• C02F2101/108

  Boron compounds · CPC title

• B01D69/02

  characterised by their properties · CPC title

• B01J20/261

  obtained by reactions only involving carbon to carbon unsaturated bonds (macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds per se C08F) · CPC title