CTS-g-PAA/ATP水凝胶制备及对染料的吸附性能

Preparation and adsorption property study of CTS-g-PAA/ATP hydrogel

以壳聚糖(CTS)、丙烯酸(AA)、凹凸棒石黏土(ATP)为原料,采用微波辐射法,通过接枝共聚合成了CTS-g-PAA/ATP水凝胶,利用FTIR和SEM分析了树脂的结构,探讨了水凝胶对亚甲基蓝的吸附性能和吸附机理。结果显示:GA、ATP和AA发生了接枝共聚反应,形成均匀的三维网络复合高吸水凝胶。在200 mL浓度为200 mg/L,加入2 mmol/L的NaCl、SDS的MB溶液中,凝胶对MB的吸附量分别147、330 mg/g。溶液pH在4~7之间时,凝胶对MB吸附量保持恒定的吸附能力,吸附量为300 mg/g。水凝胶对MB的吸附应用Freundlich方程比Langmuir方程更适合实验数据,吸附动力学符合准二级动力学模型,吸附过程属于化学吸热反应过程。

CTS-g-P AA/ATP hydrogel was prepared by graft copolymerization of chitosan(CTS),acrylic(AA),attapulgite clay(ATP)by microwave radiation.The structure of the hydrogel was analyzed by FTIR and SEM,and the adsorption mechanism and property of hydrogel to methylene blue were discussed.The results showed that the graft copolymerization of CTS,ATP and AA took place,forming a uniform three-dimensional network composite superabsorbent gel.The adsorption capacity of MB on the hydrogel was 147 mg/g and 330 mg/g,respectively,when 2 mmol/L NaCl and SDS were added into 200 mL 200 mg/L MB solution.When the solution pH was between 4 and 7,the adsorption capacity of the hydrogel to MB was constant,and the adsorption capacity was 300 mg/g.It was seen that the Freundlich model fitted the adsorption data better than the Langmuir model.The adsorption kinetics of MB by hydrogel satisfied the quasi-second-order kinetic model.