A stable Al-MOF based on pore size control strategy for efficient SF6/N2 separation

SF 6 has been widely used as an insulating medium, but it can also cause serious greenhouse effect. The efficient separation of SF 6 appears very important and challenging. A stable and scalable synthesis of Al-MOF (MOF-303) is reported in the present work, which possesses an appropriate pore size (6.79 Å) that matches the dynamic diameter of SF 6 molecules (5.2 Å). MOF-303 shows a higher adsorption capacity of SF 6 (49.70 cm 3 /g) at low pressure (10 kPa) and ambient temperature, and the excellent adsorption selectivity of SF 6 /N 2 (10:90) achieves 183.37 at ambient conditions. Meanwhile, breakthrough experiments exhibit that MOF-303 can efficiently separate high purify SF 6 form SF 6 /N 2 mixtures at ambient conditions. The relevant experimental conclusions have been further verified by theoretical calculations. The stronger binding energy between MOF-303 and SF 6 molecule should be responsible for the efficient SF 6 adsorption and separation. More importantly, the adsorption capacity of SF 6 by the particle sample has decreased, but it still exhibits excellent gas separation ability. The results will contribute to the design efficient and practical gas separation materials. • A stable Al(III)-MOF (MOF-303) was synthesized conveniently. • MOF-303 exhibits higher adsorption capacity of SF 6 over that of N 2 . • MOF-303 can efficiently separate of SF 6 from SF 6 /N 2 mixture. • GCMC simulation and DFT calculation further support the experimental results.