胺化磁性壳聚糖去除水中微量阿特拉津的研究

Removal of aqueous trace atrazine by aminated magnetic chitosan

针对水中微量阿特拉津的去除问题,采用反相悬浮聚合法制备了胺化磁性壳聚糖微粒(MCP-A),研究了其对微量阿特拉津的去除效能和吸附机理.研究结果表明:MCP-A呈球形,粒径120μm,氨基浓度5.33mmol/g,比饱和磁化强度9.15emu/g,易于磁分离;MCP-A吸附阿特拉津60min达到平衡,当阿特拉津初始质量浓度为50.4,100.5和200.2μg/L时,吸附容量分别为7.7,14.0和27.2μg/g;pH值和水温对吸附效能影响较大,较高的pH值和水温有利于MCP-A吸附阿特拉津;Langmuir,Freundlich和Sips等温式均能较好地拟合吸附等温线;MCP-A吸附阿特拉津属于吸热的物理吸附过程,吸附作用通过MCP-A的氨基与阿特拉津分子间形成氢键实现.

The purpose of this study is how to remove aqueous trace atrazine. Thus aminated magnetic chitosan particulate （MCP-A） was prepared by using inverse suspension polymerization, with the re- moval efficiency and the adsorption mechanism of trace atrazine onto MCP-A being discussed. MCP-A is spherical with its diameter of 120 ~m, and Amino content and specific saturation magnetization of MCP-A are 5.33 mmol/L and 9. 15 emu/g, respectively. MCP-A can be separated quickly with ap- plied magnetic field. The adsorption of atrazine onto MCP-A reaches equilibrium after 60min. The ad- sorption capacities at initial concentration of 50.4, 100.5 and 200.2 μg/L are 7.7, 14.0 and 27.2 μg/ g, respectively. Temperature and pH influence adsorption efficiency greatly. Higher temperature and pH are conducive to adsorption of atrazine onto MCP-A. Adsorption isotherm is well fitted by Lang- muir, Freundlich and Sips equation. The adsorption process is endothermic in nature and belongs to physical adsorption. The mechanism of adsorption is the formation of hydrogen bond between amino and atrazine molecular.