MGO/SA制备及其对含Cr(Ⅵ)污水吸附处理研究

Preparation of MGO/SA and study on adsorption of Cr(Ⅵ)in water

采用海藻酸钠(SA)溶液与磁性氧化石墨烯(MGO)共混制备复合微球(MGO/SA),研究其对水中Cr(Ⅵ)的吸附处理效果。实验表明,以海藻酸钠为包埋载体,通过添加适量致孔剂处理经磁化的氧化石墨烯,可获得一定尺寸的MGO/SA复合微球,最优制备工艺为:MGO投加量0.45 g,固化温度25℃,NaCl含量2.4 g。FTIR、SEM、VSM等表明,MGO/SA表面粗糙,呈无规则网状结构,内部含氧基团增多,吸附活性增强,且微球具有典型的S型磁滞回线,能快速从水溶液中分离。在MGO投加量为0.3 g、pH值为1条件下,处理10 mg/L的含Cr(Ⅵ)污水270 min,Cr(Ⅵ)的去除率为97.28%;复合微球对Cr(Ⅵ)的吸附过程符合准二级动力学方程。

Composite microspheres(MGO/SA)were prepared by blending sodium alginate(SA)solution with Magnetic graphene oxide(MGO),the adsorption effect of Cr(Ⅵ)in water was studied.The results showed that MGO/SA composite microspheres of a certain size could be obtained by using sodium alginate as the embedding carrier and magnetized graphene oxide treated with an appropriate amount of pore-foaming agent.The optimal preparation process was 0.45 g MGO dosage,25℃curing temperature and 2.4 g NaCl content.FTIR,SEM,VSM etc.showed that MGO/SA had rough surface,irregular network structure,increased oxygen-containing groups and enhanced adsorption activity.The microspheres have a typical S-type hysteresis loop and can be separated from aqueous solution quickly.Under the test condition of 0.3 g MGO dosage and pH value of 1,the removal rate of Cr(Ⅵ)could reach 97.28%after treating 10 mg/L Cr(Ⅵ)containing sewage for 270 min.The adsorption process of Cr(Ⅵ)by the composite microspheres conforms to the quasi-second-order kinetic equation.