壳聚糖对酸性艳橙GS的吸附平衡与动力学研究

摘要

研究了壳聚糖(CS)对水溶液中的酸性艳橙GS(ABO)染料的吸附性能,考察了温度、pH值、壳聚糖分子量对吸附性能的影响.不同温度下的动力学数据分别采用拟一级、拟二级、内扩散方程进行关联;不同温度下壳聚糖对酸性艳橙GS的吸附平衡数据分别用1angmuir、Freundlich、Tempkin模型拟合.结果表明:该吸附过程符合拟二级动力学模型;Langmuir比其它两个方程具有更高的线性;壳聚糖对酸性艳橙GS的吸附服从Arrhenius方程,吸附活化能为65.62 kJ/mol,说明了该吸附过程为化学吸附;分子量较大的壳聚糖显示出较好的吸附性能;IR检测证实了壳聚糖与酸性艳橙GS之间的交互作用.%The removal of acid brilliant orange CS(ABO) from aqueous solutions was investigated using chitesan es sorbents. The effects of temperature, pH value and chitosan molecular weight on acid brilliant orange GS removal were investigated. Kinetic data obtained at different temperatures for the adsorption of ABO onto chitosan were applied to pseudo first-order, pseudo second-order and pore diffusion equations. Three isotherms( Langmuir, Freundlich and Tempkin)were used to fit the equilibrium data at different temperatures. It was obtained that the adsorption process followed the pseudo-second-order kinetic model and Langmuir equation showed higher conformity than the other two equation. Activation energy value for the adsorption process was found to be 65.62 kJ mol-1. This indicates that the adsorption process can be assumed as chemical process. The chitosan(CS) with higher molecular weight exhibited better binding performance. The interactions between ABO and chitosan were also confirmed by FTIR analysis.