MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, PR China.
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, PR China.
J Chromatogr A. 2018 Aug 17;1563:198-206. doi: 10.1016/j.chroma.2018.05.075. Epub 2018 Jun 1.
Energy-efficient and time-saving process for recovery of hazardous dyes from wastewater is highly desired in dyeing industry. In this work, poly(N-vinyl imidazole) (PVI) gel-filled membrane adsorbers were developed for highly efficient recovery of dyes through adsorption filtration. The membrane adsorbers were fabricated via dip-coating of Nylon macroporous membranes in PVI solutions followed by quaternization crosslinking with p-xylylene dichloride (XDC). Physicochemical characterizations indicated that PVI gel was successfully filled and fixed inside the Nylon matrix. In optimized conditions. The treating capacity of membrane adsorbers to typical dye sunset yellow (25 ppm of the feed concentration) reached up to 197 mg/g with the removal ratio >99%. Both the treating capacity and the removal ratio were kept steady even when the permeation flux was as high as 1000 L/m h. The membrane adsorbers developed in this work were able to not only remove anionic dyes from water, but also separate anionic dyes from cationic ones. The zeta potential and adsorption tests showed that the electrostatic interaction between PVI gel and dye molecules was responsible for the high removal efficiencies to anionic dyes. The membrane adsorbers can be regenerated effectively with NaOH solution and demonstrated good stability in both acidic and alkaline conditions.
从废水中回收危险染料的节能且省时的工艺在染色工业中是非常需要的。在这项工作中，通过在聚（N-乙烯基咪唑）（PVI）溶液中浸涂尼龙大孔膜并随后用对二甲苯二氯（XDC）进行季铵交联，开发了用于通过吸附过滤高效回收染料的 PVI 凝胶填充膜吸附剂。物理化学特性表明，PVI 凝胶已成功填充并固定在尼龙基质中。在优化条件下，膜吸附剂对典型染料日落黄（进料浓度为 25ppm）的处理能力高达 197mg/g，去除率>99%。即使渗透通量高达 1000L/m/h，处理能力和去除率仍保持稳定。本工作中开发的膜吸附剂不仅能够从水中去除阴离子染料，还能够将阴离子染料与阳离子染料分离。动电位和吸附测试表明，PVI 凝胶与染料分子之间的静电相互作用是对阴离子染料具有高去除效率的原因。膜吸附剂可以用 NaOH 溶液有效再生，并在酸性和碱性条件下均表现出良好的稳定性。
