阳离子型木质素基水凝胶对甲基橙的吸附研究

Adsorption of Methyl Orange by Cationic Lignin-Based Hydrogel

以丙烯酰氧乙基三甲基氯化铵(DAC)为阳离子单体,通过化学改性合成了一种阳离子型木质素基水凝胶(D-LH),通过FTIR、SEM对其结构进行了表征,评价了D-LH的溶胀与消溶性能及对甲基橙的吸附性能,并通过吸附动力学、等温吸附模型、吸附热力学探讨了吸附机理。结果表明,D-LH在180 min时溶胀比为48.68 g·g^(-1),在240 min时达到消溶平衡,消溶率为98.42%;D-LH对甲基橙有较好的吸附效果,在pH值为7、吸附时间为90 min、D-LH投加量为0.1 g、甲基橙初始浓度为200 mg·L^(-1)、吸附温度为30℃的条件下,吸附量可达86.05 mg·g^(-1),该吸附过程是物理吸附与化学吸附共同作用的结果。

Taking acryloyloxyethyl trimethylammonium chloride(DAC)as a cationic monomer,we synthesized cationic lignin-based hydrogel(D-LH)by chemical modification,and characterized the structure by FTIR and SEM.Moreover,we evaluated the swelling and dissolution performances of D-LH and the adsorption performance of D-LH to Methyl Orange.Furthermore,we discussed the adsorption mechanism by adsorption kinetics,isothermal adsorption model,and adsorption thermodynamics.The results show that the swelling ratio of D-LH is 48.68 g·g^(-1) at 180 min,and D-LH reaches dissolution equilibrium at 240 min with the dissolution rate of 98.42%.In addition,the adsorption capacity can reach 86.05 mg·g^(-1) under the conditions as follows:the pH value of 7,the adsorption time of 90 min,the D-LH dosage of 0.1 g,the initial concentration of Methyl Orange of 200 mg·L^(-1),and the adsorption temperature of 30℃,indicating that D-LH has good adsorption effect to Methyl Orange.The adsorption process is the result of the comprehensive action of physical adsorption and chemical adsorption.