Process for the preparation of MOFs-porous polymeric membrane composites

Patent metadata

Field	Value
Publication number	US-9713796-B2
Application number	US-201414764071-A
Country	US
Kind code	B2
Filing date	Jan 28, 2014
Priority date	Jan 28, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

Disclosed herein is an in-situ process for the preparation of Metallic Organic Framework's (MOF's)—polymer composites at room temperature, without requirement of pre-seeding o MOF's or substrate modification. Further, the invention provides MOF-polymer composites membranes, wherein MOF forms a layer substantially covering the porosity of the membrane.

First claim

The invention claimed is:

1. An in-situ process for preparation of Metallic Organic Frameworks (MOF)-polymer composite substantially devoid of pores without pre-seeding or substrate modification, comprising the steps of:
a) subjecting a porous polymer membrane to solvent treatment for period in the range of 4 to 8 hr;
b) repeatedly treating the membrane of step (a) with ligand solution A for period in the range of 8 to 12 hrs followed by treatment with metal solution B for period in the range of 8 to 12 hrs or vice versa; and
c) repeatedly treating the membrane of step (b) with ligand solution (A) for period in the range of 8 to 12 hrs, followed by suspending the membrane in mixture of solution A and B for period in the range of 8 to 12 hrs to obtain MOF polymer composite.

2. The process according to claim 1 , wherein the solvent used in step (a) is selected from the group consisting of methanol, dimethyl form amide (DMF), ethyl alcohol (EtOH), butanol, isopropyl alcohol, n-propanol, acetonitrile, acetone, ethyl acetate or mixtures thereof.

3. The process according to claim 2 , wherein the solvent is methanol and mixture of DMF:EtOH:water (1:1:1 volume ratio).

4. The process according to claim 1 , wherein step (b) is repeated at least for two cycles and step (c) is repeated at least for three cycles.

5. The process according to claim 1 , wherein the ligand (A) is selected from the group consisting of benzene tricarboxylic acid (BTC) and 2-methyl imidazole (MIM) and the solutions are made using as solvent, methanol and mixture of DMF:EtOH:water (1:1:1 volume ratio).

6. The process according to claim 1 , wherein the metal solution (B) is selected from the group consisting of Cu(NO 3 ) 2 , copper acetate, CuSO 4 , Zn(NO 3 ) 2 , Zinc acetate or ZnSO 4 .

7. The process according to claim 1 , wherein TEA (Tri-ethyl amine) is used as catalyst for the metal solution (B) of Copper.

8. The process according to claim 1 , wherein the process is carried out at temperature ranging from 20 to 40° C.

9. The process according to claim 1 , wherein the polymer in step (a) is selected from polysulfone (PSF) and polyacrylonitrile (PAN).

10. The process according to claim 1 , wherein the MOF-polymer composite is selected from CuBTC-PSF; ZIF-8-PSF (Zinc Imidazolate framework); CuBTC-PAN and ZIF-8-PAN.

11. The process according to claim 1 , wherein the thickness of the MOF layer on the polymer membrane ranges from 10 μm-25 μm.

12. The process according to claim 1 , wherein CuBTC crystals have size ranging from 5 to 20 μm on the membrane and 200 to 500 nm inside the pores.

13. The process according to claim 1 , wherein the ZIF-8 crystals have size ranging from 5 μm to 200 nm on the membrane and 20-80 nm inside the pores.

14. Metallic Organic Frameworks (MOF)-polymer composite substantially devoid of pores without pre-seeding or substrate modification as-prepared by a process comprising the steps of:
a) subjecting a porous polymer membrane to solvent treatment for period in the range of 4 to 8 hr;
b) repeatedly treating the membrane of step (a) with ligand solution A for period in the range of 8 to 12 hrs followed by treatment with metal solution B for period in the range of 8 to 12 hrs or vice versa; and
c) repeatedly treating the membrane of step (b) with ligand solution (A) for period in the range of 8 to 12 hrs, followed by suspending the membrane in mixture of solution A and B for period in the range of 8 to 12 hrs to obtain MOF polymer composite;
wherein the thickness of the MOF layer on the polymer membrane ranges from 10 μm-25 μm.

Assignees

• Council Scient Ind Res

Inventors

• Kharul Ulhas Kanhaiyalal
• Banerjee Rahul
• Nagaraju Divya

Classifications

• B01D2323/40

  in-situ membrane formation · CPC title

• C08J2381/06

  Polysulfones; Polyethersulfones · CPC title

• C08J2333/20

  Homopolymers or copolymers of acrylonitrile (C08J2355/02 takes precedence) · CPC title

• C08J9/36

  After-treatment (C08J9/22 takes precedence) · CPC title

• B01D71/00

  Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor · CPC title