Preparation and application of functionalized graphene oxide composite membrane

Belonging to the technical field of gas separation membranes, the invention discloses a preparation method and application of a functionalized graphene oxide composite membrane. The preparation process includes: preparing an aqueous dispersion of graphene oxide by Hummer method and conducting ultrasonic dispersion; adding polyethylene glycol diamine, and carrying out heating stirring; covering a micro-filtration membrane surface with the prepared dispersion by vacuum pumping filtration; and placing the membrane into a drying oven to perform drying. The preparation method provided by the invention is simple, the prepared membrane has a thickness of less than 10nm, and the graphene interlamellar spacing is adjustable, the prepared composite membrane can be used for gas separation, and has excellent comprehensive performance. In particular, the graphene oxide composite membrane prepared from polyethylene glycol diamine with a molecular weight of 1000 has high CO2 permeation flux and CO2/CH4, CO2/N2 selectivity, mixed gas test under a dry condition finds that the CO2 permeation flux can reach 220GPU, the CO2/CH4 selectivity is 42, and the CO2/N2 selectivity is 55.