A High‐Performance N<sub>2</sub>‐Selective MXene Membrane with Double Selectivity Mechanism for N<sub>2</sub>/CH<sub>4</sub> Separation
Guangyu Xing, Shenzhen Cong, Bo Wang, Zhihua Qiao, Qinghua Li, Chang Cong, Ye Yuan, Menglong Sheng, Yunqi Zhou, Fei Shi, Jun Ma, Yurui Pan, Xinlei Liu, Song Zhao, Jixiao Wang, Zhi Wang
Abstract
Abstract Membrane‐based separation process for unconventional natural gas purification (mainly N 2 /CH 4 separation) has attracted more attention due to its considerable economic benefits. However, the majority of separation membranes at this stage, particularly N 2 ‐selective membranes, achieve the desired separation target by mainly relying on the diffusivity‐selectivity mechanism. To overcome the limitation of a single mechanism, 2D lamellar MXene membranes with a double selectivity mechanism are prepared to enhance N 2 permeance and N 2 /CH 4 selectivity via introducing unsaturated metal sites into MXene, which can form specific interactions with N 2 molecules and enhance N 2 permeation. The resulting membranes exhibit an inspiring N 2 /CH 4 separation performance with an N 2 permeance of 344 GPU and N 2 /CH 4 selectivity of 13.76. The collaboration of the double selectivity mechanism provides a new idea for the development of a novel N 2 ‐selective membrane for N 2 removal and CH 4 purification, which further broadens the application prospects of membrane separation technology in the field of unconventional natural gas purification.