| Ethylene is one of the largest chemical products in the world.In the production of polymer-grade ethylene,the presence of acetylene impurities will cause the catalyst poisoning during ethylene polymerization,and thus reduce the quality of the polyethylene.Therefore,separation acetylene from ethylene is of great significance.Among the traditional separation methods,pressure swing adsorption method has been widely used because of its advantages such as less investment,low energy consumption,and easy operation.Commonly used sorbents include:molecular sieves,carbon materials,silica sols,and metal-organic frameworks（MOFs）.Compared with other adsorbents,MOFs have fine controlled pore structure,gate-opening effect of flexible structure and unsaturated metal sites,which make them exhibits great potential in acetylene/ethylene separation.This article is focus on the M3[（M4Cl）3（BTT）8]2(M2+=Mn、Fe、Co、Cu)series materials,these materials contented unsaturated metal sites and have similar three-dimensional framework which were constructed by1,3,5-benzenetristetrazolate（H3BTT）and different metal atoms.Their rich unsaturated metal sites and large adsorption capacity is good for efficient separation of acetylene-ethylene mixtures.The main contents and conclusions in this thesis include:（1）Firstly,the synthesis conditions of M-BTT series materials were carefully investigated,and their structural stability were detailed studied.The best synthesis conditions were obtained,and the synthesized samples show good stability and crystal structure.（2）Secondly,single-component gas adsorption tests,and IAST selectivity calculations and acetylene/ethylene gas mixtures breakthrough experiments were performed on M-BTT series materials.IAST calculation results show that Fe-BTT has the higher acetylene/ethylene adsorption selectivity.Fe-BTT has the highest separation ability for acetylene/ethylene mixtures in the real breakthrough experiment,and high purity of ethylene is efficient separated from the mixtures. |
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