三维KIT-6分子筛对乙烯乙烷吸附分离的研究

Study on 3D-mesoporous KIT-6 for ethylene-ethane adsorptive separation

采用水热法合成三维KIT-6分子筛,以KIT-6为载体,采用等体积浸渍法负载Ag NO3制备乙烯/乙烷分离的π络合吸附剂,通过氮气吸附脱附、X射线衍射和X射线能谱分析对吸附剂进行表征,采用自制设备测定了π络合吸附剂的乙烯乙烷吸附等温线和乙烯吸附动力学曲线,相应的乙烯乙烷吸附热用克劳修斯-克拉伯龙方程求得。结果表明,Ag NO3最佳负载量为29%,在303.15 K、0.6 MPa下,络合吸附剂的乙烯吸附量高达47 m L/g,分离系数为3.3,乙烯吸附热值显示乙烯与吸附剂的作用是介于物理吸附和化学吸附之间的π络合吸附,乙烯在络合吸附剂上传质较快,具有一定的应用前景。

3D-mesoporous KIT-6 was prepared by hydrothermal synthesis method,π-complexing adsorbent for ethylene/ethane separation was synthesized by the incipient wetness impregnation method with KIT-6 as carrier and silver nitrate as active ingredient.The adsorbent was characterized by N 2 adsorption-desorption,X-xay diffraction and X-ray EDS analysis.The adsorptive isotherm of ethylene-ethane and the adsorptive kinetics curves of ethylene were determined by self-made equipment,and the corresponding adsorption heat of ethylene and ethane are calculated from the Clausius-Clapeyron equation.The result shows that the best loading of AgNO 3 is 29%,the adsorption amount of ethylene on the Ag-KIT-6 adsorbent can be reached 47 mL/g and separative factor is 3.3 at 303.15 K and 0.6 MPa,the value of adsorption heat of ethylene suggests that the interaction of ethylene with Ag-KIT-6 isπ-complexation adsorption between physisorption and chemisorption.And the diffusion performance of ethylene on complexing adsorbent exhibits excellent,which has a certain application prospect.