Enhanced CO<sub>2</sub> Separation by Functionalized g-C<sub>3</sub>N<sub>4</sub> Nanosheets as Composite Filler to Fabricate Mixed Matrix Membranes
Zhenhua Niu, Yuanyuan Wang, Yangyang Dai, Suyue Zhong, Jinyun Li, Jinyun Li, Peng Mu, Jian Li, Jian Li
Abstract
Membrane separation technology has become a very effective separation technology for CO 2 reduction, saving about 90% of energy consumption. However, the CO 2 separation performance of gas separation membranes is limited by the “trade-off” between permeance and selectivity in the separation process. Herein, g-C 3 N 4 -GO/Pebax-1657 MMMs (mixed matric membranes) were prepared by a solution casting method by combining graphene oxide (GO) nanosheets with g-C 3 N 4 nanosheets as composite fillers, and the membrane possesses excellent thermal stability and mechanical properties. Among them, GO nanosheets containing abundant functional groups were used to repair nonselective defects in g-C 3 N 4 nanosheets (amide bonds were formed between them). The prepared g-C 3 N 4 -GO 0.30 /Pebax MMM possesses excellent CO 2 separation performance (CO 2 permeance of 815.11 GPU and selectivity of 48.37 for CO 2 /N 2 separation; CO 2 permeance of 737.99 GPU and selectivity of 44.94 for CO 2 /CH 4 separation). This study provides theoretical and experimental guidance for the design and preparation of a practical CO 2 separation membrane.