Carbon dioxide gas separation membrane, method for manufacturing same, and carbon dioxide gas separation membrane module

A CO2 gas separation membrane, comprising:

• a first layer (A) including at least one alkali metal compound selected from the group consisting of an alkali metal carbonate, an alkali metal bicarbonate and an alkali metal hydroxide, and a first resin in which a polymer having a carboxyl group has been crosslinked;
• a second layer (B) including at least one alkali metal compound selected from the group consisting of an alkali metal carbonate, an alkali metal bicarbonate and an alkali metal hydroxide, and a second resin having a structural unit derived from a vinyl ester of a fatty acid;
• and
• a hydrophobic porous membrane (C),
• wherein the polymer having a carboxyl group is a polyacrylic acid homopolymer, a polyitaconic acid homopolymer, a polycrotonic acid homopolymer, or a polymethacrylic acid homopolymer, and
• the second resin is a polyvinyl alcohol, a vinyl alcohol-ethylene copolymer, a vinyl alcohol-acrylic acid copolymer, a vinyl alcohol-methacrylic acid copolymer, or a vinyl alcohol-vinylsulfonic acid copolymer.