Study on efficient separation of SF6/N2 mixture using a hydrothermally stable metal-organic framework
(2.State Key Laboratory of Separation Membranes and Membrane Processes, Tianjin Polytechnic University, Tianjin, China 300387)
【Abstract】The efficient separation of the SF6/N2 mixture has important practical significance for the recovery of SF6 gas and the reduction of the greenhouse effect caused by its direct discharge. In this work, a metal-organic framework (Cu-MOF-OMe) was prepared with two different types and properties of pores. It possesses dually-functionalized characteristics of coordinatively unsaturated metal sites and methoxy groups, which exhibits good hydrothermal stability and adsorptive regenerability. This material also shows excellent separation performance for the SF6/N2 mixture. At 298 K and 105 Pa, the observed adsorption selectivity (361) and sorbent selection parameter (SSP) value (780) are higher than those of various porous materials reported so far. Theoretical calculation results indicate that the underlying reason of such excellent separation properties is attributed to the cooperative effects of the open Cu sites in the hydrophilic pores and the abundant methoxy groups in the hydrophobic pores. The findings may provide valuable foundation for developing highly efficient materials for practical of SF6/N2 separation.
【Keywords】 metal-organic frameworks; unsaturated metal sites; sulfur hexafluoride; nitrogen; separation;
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