双金属MOF-74的合成及其气体吸附分离性能研究

Synthesis of bimetallic MOF-74and its gas adsorption and separation properties

采用溶剂热法合成了同时含Co、Ni的双金属MOF-74材料,利用X射线衍射仪、扫描电子显微镜、N2物理吸附仪、电感耦合等离子发射光谱仪等表征手段分析了材料的形貌、结构及性质,并对其在室温、0~100kPa条件下的CO2吸附性能及CO2/N2分离性能进行了研究。结果表明,双金属MOF-74保持了MOF-74的晶型结构,但晶体尺寸有所减小。气体吸附分离测试结果表明:Ni25Co-MOF-74对CO2的吸附量最大,达到4.77mmol/g,较单金属Co-MOF-74提高了13.30%左右;Ni25Co-MOF-74对CO2/N2的理想分离系数为25,较Co-MOF-74提高了66.67%左右。经过4次循环实验Ni25Co-MOF-74的CO2吸附量仍为4.75mmol/g,表现出优异的再生性能。

Bimetallic MOF-74materials containing both Co and Ni were synthesized by solvothermal method.The structure,morphology and adsorption properties were characterized by XRD,SEM,N2gas adsorption and ICPAES.Meanwhile,the CO2adsorption and CO2/N2separation performances of the materials at room temperature and 0~100kPa were studied.The result showed that bimetallic MOF-74materials retained the same crystal structure as the single metal MOF-74,but the morphology changed and the crystal size decreased.Results of CO2adsorption test showed that the bimetallic material Ni25Co-MOF-74exhibited the largest CO2adsorption capacity of 4.77mmol/g,which was 13.30%higher than that of Co-MOF-74,and the ideal separation factor for CO2/N2reached 25,which was 66.67%higher than that of Co-MOF-74.The CO2adsorption capacity of Ni25Co-MOF-74after four cycles remained 4.75mmol/g,therefore implying excellent regeneration performance.