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According to Sinochem New Network, achieving large-scale production of new types of separation materials in order to reduce the energy consumption associated with gas separation has always been a challenge that the energy and chemical industry needs to overcome. Recently, a team led by Professors Gu Xuehong and Wang Xuerui from Nanjing Tech University developed a new strategy based on \"embryo zeolite-mediated film splicing,\" enabling the large-scale production of high-performance zeolite molecular sieve membranes and providing \"precision filters\" for industrial gas separation. A zeolite molecular sieve membrane is essentially a sub-nanometer-scale \"gas molecular sieve\" whose surface is covered with ultra-small pores that allow only molecules of specific sizes to pass through, thereby enabling precise separation. “There are two major challenges in the preparation of traditional zeolite molecular sieve membranes. First, the membrane layer is too thick, which results in high resistance for gas molecules to pass through the membrane and slows down their movement. Second, when scaling up from laboratory-grade membrane samples to industrial-grade membrane products, defects are likely to occur, thereby significantly reducing the separation efficiency. ”Gu Xuehong explained. To address these issues, the research team spent 5 years conducting in-depth studies and proposed a new strategy of \"embryo zeolite-mediated seam synthesis membrane,\" which successfully solved these two major challenges. Dr. Yue Kai, a member of the research team, used an illustrative analogy: “Eliminating the gaps in traditional membrane layers is like paving asphalt on a gravel road, while the new approach is like using a ‘needle and thread’ to precisely ‘sew’ zeolite molecular sieve crystals at the atomic level, creating a separation membrane with a ‘seamless’ structure.” ” Based on this strategy, the team achieved three major breakthroughs. Wang Xuerui explained that, first, the thickness of the zeolite molecular sieve membrane has been reduced to 560 nanometers, which lowers the resistance to gas penetration; second, the separation selectivity between carbon dioxide and methane is as high as 158, meaning that out of every 300 gas molecules that pass through, no more than 2 are methane molecules; third, a membrane module covering 0.5 square meters was developed, consisting of 102 hollow fiber molecular sieve membranes each 40 centimeters long, thereby enabling the transition from laboratory-scale samples to industrial-grade components. Tests have shown that this strategy is applicable to three zeolite molecular sieves with different topologies listed by the International Zeolite Association, demonstrating good universality. The amplified preparation of the membrane is just the first step; what really matters is whether it can operate stably in a real industrial environment. The team tested the membrane modules under biogas purification conditions containing 2500 ppm of hydrogen sulfide and saturated humidity. Test results show that the membrane module operated stably for over 220 days, enabling simultaneous permeation of carbon dioxide, water, and hydrogen sulfide, and withstood harsh operating conditions. Gu Xuehong stated that this achievement provides a viable technical approach for the application of zeolite molecular sieve membranes in industrial gas separation applications such as helium extraction from natural gas, carbon removal from natural gas (biogas), and isomer separation. Currently, the team is working to further enhance the technology in order to enable its wider application in industrial settings.