含甲基纤维素的NaA沸石膜的制备和表征  

Preparation and characterization of NaA zeolite membrane with methylcellulose

作　　者：刘光瑞 杨建华[1] 王磊 鲁金明[1] 张艳[1] 王金渠[1] LIU Guangrui;YANG Jianhua;WANG Lei;LU Jinming;ZHANG Yan;WANG Jinqu(Faculty of Chemical,Environment and Biological Science and Technology,Dalian University of Technology,Dalian 116000,Liaoning,China)

机构地区：[1]大连理工大学化工与环境生命学部

出　　处：《化工进展》2019年第12期5449-5456,共8页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(21776032)

摘　　要：NaA沸石膜具有规则的孔道结构,利于分子传输,在有机物脱水领域有一定的应用。为使沸石膜生长更连续均匀,提高渗透汽化性能,本文以甲基纤维素作为空间限制剂加入合成液,探究碱度、晶化温度以及晶化时间对膜的影响,按最优条件制备合成液,并依据质量比m(MC)∶m(H2O)=1∶100添加甲基纤维素,制备NaA沸石膜。表征方法采用XRD、SEM和渗透汽化3种方式,结果表明添加甲基纤维素的沸石膜表面结构完整,生长致密且性能优良,在75℃下对0.6mol/L的NaCl水溶液做渗透汽化测试时,通量达8.33kg/(m^2·h),盐离子截留率为99.95%。在0.6mol/L的NaCl的水溶液中测试72h,结果表明添加甲基纤维素的NaA沸石膜时间依存性更好,通量保持在8.30kg/(m^2·h)左右,离子截留率稳定在99.90%。渗透汽化分离ω(C2H6O)=90%乙醇的水溶液,随着温度从60℃升高到75℃,沸石膜的通量由1.55kg/(m^2·h)升高到2.56kg/(m^2·h),渗透侧水含量保持在99.90%左右。The NaA zeolite has a regular pore structure and strong hydrophilicity which make it a favorable material for molecular transport. Favorable characteristics of this material can be used for the development of NaA zeolite membrane with an excellent selectivity for dehydration of organic matter.Secondary growth method was employed to improve the pervaporation performance of NaA zeolite membrane. The effects of alkalinity, crystallization temperature and crystallization time were investigated.The synthetic fluid was prepared according to the optimal conditions. A NaA zeolite membrane was prepared by adding methylcellulose and water with a ratio of 1∶100. The SEM, XRD and pervaporation performance tests showed that the NaA zeolite membrane prepared by the improved method has a dense growth, compact structure and excellent pervaporation performance. The synthesized membrane exhibited a high flux and salt rejection of 8.33 kg/(m^2·h) and 99.95% at 75℃ for 0.6 mol/L of NaCl aqueous solution respectively. The results showed that the NaA zeolite membranes for the desalination of 0.6 mol/L of NaCl solution displayed a good stability over aperiod of 72 hours while the fluxremains constantat 8.30 kg/(m^2·h)with a rejection rate of 99.90%. Moreover, the aqueous solution of ω(C2 H6 O) = 90% ethanol was separated by pervaporation at a temperature of 60℃ to 75℃. The flux of the zeolite membrane was increased from1.55 kg/(m^2·h) to 2.56 kg/(m^2·h). The rejection rate was maintained around 99.90%.

关 键 词：NAA沸石膜 甲基纤维素 渗透汽化 脱盐 二次生长法 

分 类 号：TQ9[化学工程]