Method for producing gas separation membrane, and gas separation membrane
A method for producing a gas separation membrane includes a step of leaving a dispersion liquid to stand still, the dispersion liquid being obtained by mixing zeolite microcrystalline bodies formed from MFI zeolite and graphene oxide with pure water, and covering the periphery of the zeolite microcrystalline bodies with the graphene oxide; a step of drying the dispersion liquid after being left to stand to obtain a powder; a step of subjecting the powder to a reduction treatment of the graphene oxide by means of heating; and a step of pressure-forming the powder after the reduction treatment so as to be formed into a membrane form.
1 . A method for producing a gas separation membrane, the method comprising:
a step of leaving a dispersion liquid to stand still, the dispersion liquid being obtained by mixing zeolite microcrystalline bodies formed from MFI zeolite and graphene oxide with pure water, and covering an outer peripheral surface of each zeolite microcrystalline bodies with the graphene oxide;
a step of drying the dispersion liquid after being left to stand to obtain a powder;
a step of subjecting the powder to a reduction treatment of the graphene oxide by means of heating;
a step of performing a heating treatment at a temperature higher than the heating temperature for the reduction treatment and forming nanowindows in the graphene after being reduced; and
a step of pressure forming compression molding the powder after the reduction treatment so as to be formed into a membrane,
wherein the dispersion liquid is left to stand still in a state of being adjusted by a pH adjusting agent to a pH in the range of 3.6 to 11.0.
2 . The method for producing a gas separation membrane according to claim 1 ,
wherein the pH adjusting agent is ammonium chloride, and
the pH of the dispersion liquid is adjusted by the pH adjusting agent to the range of 3.6 to 4.0.
3 . The method for producing a gas separation membrane according to claim 1 , wherein the heating treatment for forming nanowindows is carried out in a temperature range of 200° C. to 600° C. for about 5 minutes to 50 hours.
4 . The method for producing a gas separation membrane according to claim 1 , wherein the compression molding is carried out by applying a pressure of 5 MPa to 40 MPa.