微流控法制备的多孔微球对Cr(Ⅵ)的吸附性能

利用玻璃毛细管搭建单级微流控装置制备单分散水包油（O/W）乳液，以乳液为模板，紫外光照射乳液引发自由基聚合，成功制备了单分散甲基丙烯酸甲酯/甲基丙烯酸二甲基氨基乙酯（MMA/DMAEMA）多孔微球。微球粒径偏差系数（CV）值小于5%，单分散性良好。研究了MMA/DMAEMA多孔微球对Cr(Ⅵ)的吸附性能、再生吸附性能、吸附机理。结果表明：pH对微球吸附Cr(Ⅵ)的量有较大影响，当pH=3时，微球对Cr(Ⅵ)吸附率达到52.9%；循环4次后微球吸附率基本不降低，循环性能好；微球吸附符合准二级动力学模型，属于化学吸附；微球等温吸附符合Langmuir模型，属于单分子层吸附。

Preparation of porous microspheres by microfluidic method and its adsorption properties for Cr(VI)

The monodisperse oil-in-water (O/W) emulsions were prepared by using a glass capillary tube to build a single-stage microfluidic device. By using the emulsions as a template, the ultraviolet light irradiated the emulsions to initiate the free radical polymerization, and the methyl methacrylate/dimethylaminoethyl methacrylate (MMA/DMAEMA) porous microspheres were successfully prepared. The particle deviation coefficient (CV) value of the microspheres was less than 5%, and the monodispersity was good. The adsorption mechanism, regenerative adsorption property and adsorption property of MMA/DMAEMA porous microspheres for Cr(VI) were investigated. The results showed that the pH had a great influence on the adsorption rate of microspheres. When the pH value was 3, the adsorption rate of microspheres reached 52.9%. After the fourth cycles, the adsorption rate was basically not reduced, and the cycle performance was good. The microsphere adsorption conformed to the quasi-secondary kinetic model and belonged to the chemical adsorption. The microsphere isotherm adsorption conformed to the Langmuir model and belonged to the monolayer adsorption.