羧基化石墨烯/壳聚糖复合材料对Cr(Ⅵ)的吸附研究

Adsorption of Cr(Ⅵ)by Carboxylated Graphene/Chitosan Composites

氧化石墨烯/壳聚糖复合材料因比表面积大,吸附性能好受到广泛研究。通过溶液共混法制备了羧基化石墨烯/壳聚糖复合材料,并考察其对Cr(Ⅵ)的吸附性能。研究结果表明:复合材料对Cr(Ⅵ)的吸附量随pH值的上升而下降,对100 mg/L的Cr(Ⅵ)最佳吸附条件是pH值为2,复合材料使用量为0.8 g/L,吸附温度50℃,吸附时间250 min,此时吸附量为119.20 mg/g,吸附率为95.36%。吸附过程符合Langmuir等温线和拟二级动力学模型,说明吸附为单层吸附和化学吸附。

Graphene oxide/chitosan composites have been widely studied due to their large specific surface area and good adsorption properties.Carboxylated graphene/chitosan composites were prepared by solution blending method,and their adsorption properties for Cr(Ⅵ)were investigated.The research results show that the adsorption amount of Cr(Ⅵ)by the composite material decreases with the increase of pH value.The optimum adsorption condition for 100 mg/L Cr(Ⅵ)is pH value of 2,and the usage amount of the composite material is 0.8 g/L,adsorption temperature is 50℃,adsorption time is 250 min,the adsorption capacity and the adsorption rate are 119.20 mg/g and 95.36%.The adsorption process conforms to the Langmuir isotherm and the pseudo-second-order kinetic model,indicating that the adsorption is monolayer adsorption and chemical adsorption.