Author(s): Hao Quanlong, Qiao Hua, Zhou Congzhi, Peng Wei, Zhang Kai, Lu Sheng, Fu Gaoyang, Department of National Defence Architecture Planning & Environmental Engineering, Logistical Engineering University
Pages: 2687-2692
Year: 2016 Issue:  5
Journal: Chinese Journal of Environmental Engineering
Keyword:  fulvic acid; TNT; adsorption kinetic; desorption; hysteresis index;
Abstract: In order to study the rules for TNT adsorption / desorption on fulvic acid( FA),the adsorption kinetics and adsorption / desorption were investigated by using batch equilibrium experiments. The results indicated that the adsorption process of TNT on FA was divided into a fast and a slow stage,and that adsorption equilibrium occurred after 18 h. The pseudo-second-order model was the best model to describe the adsorption kinetics of TNT on FA,followed by the Elovich model and intra-particle diffusion model. The adsorption-desorption isotherms of TNT on FA were predicted accurately by the Freundlich model. Nonlinear adsorption occurred in the case of TNT on FA because the parameter 1 / n of the adsorption isotherm fitted by the Freundlich model was less than 1. The hysteresis index( HI) value was 1. 06,indicating that the desorption process of TNT from FA produced a desorption hysteresis effect.