改性UiO-66材料的制备及二甲苯异构体吸附性能研究  

Synthesis of modified UiO-66 and their adsorption properties of xylene isomers

作　　者：梁梦迪 任秀秀 陈乐[1] 徐荣[1] 张琪[1] 戚律 马文中[1,2] 钟璟 LIANG Meng-di;REN Xiu-xiu;CHEN Le;XU Rong;ZHANG Qi;QI Lyu;MA Wen-zhong;ZHONG Jing(Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology,School of Petrochemical Engineering,Changzhou University,Changzhou 213164,China;Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials,School of Materials Science and Engineering,Changzhou University,Changzhou 213164,China)

机构地区：[1]常州大学石油化工学院,江苏省绿色催化材料与技术重点实验室,江苏常州213164 [2]常州大学材料科学与工程学院,江苏省环境友好高分子材料重点实验室,江苏常州213164

出　　处：《高校化学工程学报》2020年第6期1378-1385,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：江苏高校‘青蓝工程’资助;江苏省高校自然科学研究重大项目(18KJA530001);常州大学科研启动基金(ZMF19020297)。

摘　　要：采用溶剂热法成功合成UiO-66、UiO-66─NH2和UiO-66─(CF3)2。通过X射线衍射仪(XRD)和扫描电镜(SEM)对材料进行晶型和形貌表征;测定单组份二甲苯异构体在UiO-66及改性材料上的吸附等温线及速率曲线;通过动态突破实验,考察温度对三元等摩尔二甲苯异构体混合物在UiO-66及改性材料上吸附性能的影响。结果表明,UiO-66和UiO-66─NH2对二甲苯异构体的吸附均符合二级动力学模型,而UiO-66─(CF3)2由于较大侧链的位阻作用,其吸附更符合一级动力学模型;3种材料均具有反相选择性,吸附选择性遵循:邻二甲苯(OX)>间二甲苯(MX)>对二甲苯(PX);随温度的升高,125℃下UiO-66─NH2对OX/PX、OX/MX选择性均高于未改性的UiO-66;而双三氟甲基由于孔内扩散抑制作用,选择性降低。因此,高温条件下对UiO-66材料进行氨基改性是工业过程中分离二甲苯异构体获得高吸附分离性能的可行方法。UiO-66 and its modified derivatives with─NH2 and─(CF3)2 groups were successfully synthesized by a solvothermal method.The crystal structure and morphology of these materials were characterized by XRD and SEM,and their xylene isomer adsorption isotherms and rates were measured.Dynamic breakthrough experiments were used to investigate temperature effects on the adsorption of ternary equimolar mixtures.The results show that the adsorption of xylene isomers by UiO-66 and UiO-66─NH2 follows the second-order kinetic model,while the results of UiO-66─(CF3)2 fit the first-order kinetic model due to the steric hindrance of the larger side chain.All three materials showed reverse shape selectivity,and the adsorption selectivity was OX>MX>PX.With the increase of temperature,the selectivity of UiO-66─NH2 for OX/PX and OX/MX at 125℃were higher than that of UiO-66.Trifluoromethyl had no selectivity due to diffusion inhibition.Therefore,under high temperature conditions,amino modification of UiO-66 is a feasible method for separating xylene isomers to obtain high separation performance for industrial application.

关 键 词：UiO-66 改性材料 二甲苯异构体 吸附 突破曲线 

分 类 号：TQ028.3[化学工程]