Polymeric membranes and their derivatives for H2/CH4 separation: State of the art

[Display omitted] •Research progress of polymeric membranes and their derivatives for H2/CH4 has been critically reviewed and discussed.•Polymeric membranes and CMS membranes exhibit outstanding H2/CH4 separation performances.•MMMs present high H2 permeability but relatively low H2/CH4 selectivity.•Perspectives and future research directions for H2/CH4 separation membranes were proposed. The hydrogen economy becomes an important route in approaching carbon neutrality. Compared to conventional methods, membrane separation possesses combined merits, including energy-saving, convenience, and economic efficiency. In the past few years, significant progress has been made in hydrogen (H2)/methane (CH4) separation membranes, but a systematic review of membranes for this application is still lacking. Herein, the research progress of polymeric membranes, mixed matrix membranes (MMMs), and carbon molecule sieve (CMS) membranes has been critically reviewed and discussed. Research results from the latest literature are summarized and analyzed. It is found that polymeric membranes and CMS membranes exhibit outstanding H2/CH4 separation properties, while MMMs, although widely investigated, show lower performance. The perspectives and future research directions for H2/CH4 separation membranes were also presented. This review provides an in-depth understanding of the latest research and offers valuable inspirations for theoretical research and practical applications for the H2/CH4 separation membranes.