An exploration of novel natural gas leak detection based on the efficient CH4/N2 separation of polymer blend membrane

The CH 4 /N 2 high-efficiency membrane separation technology is capable of effectively enriching CH 4 from natural gas, and holds great potential for application in the fields of biogas purification and natural gas pipeline leak detection. However, preparing high-performance separation membranes is challenging due to the similarity between CH 4 and N 2 molecules. To enhance the CH 4 /N 2 separation performance, block polyetheramide copolymer (Pebax)/EVA blended membranes were fabricated in this study. Additionally, a novel gas leakage detection tube was prepared. The EVA14 (14 wt% VA) membrane exhibits an optimal transport-facilitated channel among a series of pure EVA membranes, resulting in a CH 4 permeability of 21.41 Barrer and CH 4 /N 2 selectivity reaches 1.80 under mixed-gas feed conditions at 35 °C. The CH 4 permeability of Pebax/EVA (30 wt%) reaches 120.5 Barrer by physical blending, and the CH 4 permeability is increased by 191 % in comparison with pure EVA14 membrane. The Pebax/EVA (10 wt%) membrane exhibits the optimum CH 4 /N 2 selectivity, and compared with pure EVA membrane increased by 35.5 %. EVA and Pebax polymers are blended for the first time for CH 4 /N 2 separation, and the blending of block polyetheramide copolymer intensifies the membrane's separation performance comprehensively. The natural gas leak detection tube was fabricated with a membrane, offering a new and efficient CH 4 /N 2 separation strategy.