基于纤维素凝胶层修饰的高通量分离膜及其染料/盐分离性能  

High flux separation membranes based on cellulose gel layer modification and their dye/salt separation properties

作　　者：张子旭 杨景 林立刚 唐峰铃 马文松 刘子天 王启莹 尚惠阳 吴昊 ZHANG Zixu;YANG Jing;LIN Ligang;TANG Fengling;MA Wensong;LIU Zitian;WANG Qiying;SHANG Huiyang;WU Hao(State Key Laboratory of Membrane Separation and Membrane Process,School of Materials Science and Engineering,Tiangong University,Tianjin 300387,China)

机构地区：[1]天津工业大学材料科学与工程学院,省部共建分离膜与膜过程国家重点实验室,天津300387

出　　处：《膜科学与技术》2024年第6期71-77,87,共8页Membrane Science and Technology

基　　金：国家自然基金项目(22078244);天津工业大学国家级大学生创新创业训练计划资助项目(202310058013)。

摘　　要：纺织工业产生的大量含盐染料废水已成为全球的环境问题之一,因此,迫切需要具有高通量的染料/盐选择性分离膜进行废水处理.本研究采用非溶剂致相分离法(NIPS)制备聚偏氟乙烯(PVDF)基膜,通过多巴胺和羧甲基纤维素共沉积反应在膜表面引入羧甲基纤维素,然后利用层层交联的方式在膜表面构建具有三维网络结构的羧甲基纤维素凝胶层,在凝胶层制备过程中原位引入无机银纳米粒子,银纳米粒子能够起到骨架支撑的作用,避免了压力下凝胶层的坍塌,功能凝胶层的构建同步提升膜的渗透性能及选择性.实验发现,当羧甲基纤维素质量浓度为1 g/L时所制备的M CMC Ag膜各方面性能较优,其水通量达到275.11 L/(m^(2)·h),在不同浓度的染料/盐二元体系(刚果红/NaCl混合液)分离测试中,M CMC Ag膜对染料的截留率高达95%以上,并且对于无机盐的截留率低于9.5%.在染料溶液的循环测试中,M CMC Ag膜的稳定性良好,对循环测试的刚果红溶液维持了高于285 L/(m^(2)·h)的渗透通量.The large amount of salt-containing dye wastewater generated by the textile industry has become one of the global environmental problems,so there is an urgent need for dye/salt selective separation membranes with high flux for wastewater treatment.In this study,poly(vinylidene fluoride)(PVDF)-based membranes were prepared by non-solvent-initiated phase separation(NIPS),carboxymethylcellulose was introduced on the membrane surface through the co-deposition reaction of dopamine and carboxymethylcellulose,and then a carboxymethylcellulose gel layer with three-dimensional network structure was constructed on the surface of the membrane by using layer-by-layer cross-linking,and inorganic silver nanoparticles were introduced in situ in the process of the preparation of the gel layer,which could play a role of backbone support to avoid the collapse of the gel layer under pressure,and the construction of the functional gel layer synchronously enhanced the permeability and selectivity of the membrane.It was found that M CMC Ag membranes prepared at a carboxymethylcellulose concentration of 1 g/L were superior in all aspects of performance,and its water flux reached 275.11 L/(m^(2)·h),and in the separation test of the binary system of dye/salt at different concentrations(Congo red/NaCl mixture solution),the rejection rate of the dye was more than 95%,and the rejection rate of the inorganic salts was less than 9.5%.The M CMC Ag membrane was well stabilised in the cycling test of the dye solution and maintained a permeate flux higher than 285 L/(m^(2)·h)for the cycling test of the Congo red solution.

关 键 词：亲水改性 多巴胺 羧甲基纤维素 凝胶层 染料/盐分离 

分 类 号：TQ028.8[化学工程]