面向氢气/甲烷分离分子筛膜微结构调控的研究进展

Hydrogen energy has the advantages of high combustion value and zero carbon emissions. The development of hydrogen energy technology is an important measure to realize the"carbon peak and carbon neutral"strategy. The current hydrogen is mainly produced from the water shift reactions of natural gas, by-produced from the fabrication of ethylene and propylene in the petroleum industry and purge gas. Separation of hydrogen from hydrocarbons (methane as the typical composition) is necessary for the natural gas and petroleum- based hydrogen production. Separation technologies of H₂/CH₄ mixture include pressure swing adsorption, cryogenic distillation and membrane separation. Molecular sieving membranes [zeolite and metal organic frameworks (MOFs)] become the most potential ones for the energy-saving separation of H₂/CH₄ mixtures due to their advantages of precise molecular sieving, high separation performance and anti-aging properties. The strategies of microstructure regulation and H₂/CH₄ separation performance of molecular sieving membranes and the relationship of structure-performance were stated in this review. Opportunities and challenges of molecular sieving membranes were analyzed for H₂/CH₄ separation. In order to quantify and compare the separation performance of different membrane materials, the performance data of molecular sieving membranes for H₂/CH₄ separation were summarized in 2008 Robeson upper bound chart that was previously used for the comparison of polymeric membranes. The economically available target regions of the separation performance of molecular sieving membranes for hydrogen separation were also predicted.