Hybrid polymer membrane
The present invention relates to CO 2 capture from gas mixtures by use of gas separation membranes. In particular, the invention relates to a gas separation membrane comprising: a gas permeable or porous support layer; and at least one CO 2 selective polymer layer comprising carbonic anhydrase (CA) enzymes fixed within the at least one CO 2 selective polymer layer. The present invention also relates to the method of separating CO 2 from a gas and to the use of the gas separation membrane.
1. A gas separation membrane comprising:
a dense gas permeable support layer or porous support layer; and
at least one CO 2 selective polymer layer comprising carbonic anhydrase (CA) enzymes fixed within the at least one CO 2 selective polymer layer, wherein the at least one CO 2 selective polymer layer is a biopolymer layer formed by copolymerisation of chemically modified CA enzymes and monomers; and wherein the at least one CO 2 selective polymer layer is based on a hydrophilic polymer.
2. The gas separation membrane according to claim 1 , where the at least one CO 2 selective polymer layer further comprises amine groups.
3. The gas separation membrane according to claim 1 , wherein the CA enzymes are thermostable enzymes resistant to temperature of at least 50° C.
4. The gas separation membrane according to claim 1 , wherein the hydrophilic polymer is selected from polyvinyl alcohol, polyacrylamide, polyvinyl amide, alginate, chitosan and polyvinyl amine.
5. The gas separation membrane according to claim 1 , further comprising a protective layer made of high gas and water vapour permeability material coated on top of the CO2 selective polymer layer.
6. The gas separation membrane according to claim 1 , wherein the at least one CO 2 selective polymer layer has a thickness in the range from 0.1 to 10 μm.
7. The gas separation membrane according to claim 1 , wherein the at least one CO 2 selective polymer layer has multilayer structure formed by at least two layers of the CA enzyme modified polymer layers.
8. The gas separation membrane according to claim 6 , wherein the CO 2 selective polymer layer has a thickness in the range from 0.1 to 5 μm.
9. The gas separation membrane according to claim 1 , wherein the at least one CO 2 selective polymer layer has multilayer structure formed by at least a CA enzyme modified polymer layer and an amine-containing polymer layer.