Kinetics and Thermodynamics Characteristics of Cationic Yellow X-GL Adsorption on Attapulgite/Rice Hull-Based Activated Carbon Nanocomposites

摘要

Attapulgite;'activated carbon (ATP/AC) nanocomposites were prepared by the calcination of ATP and rice hull. ATP/ AC nanocomposites were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy analysis. The kinetic and thermodynamic parameters of the adsorption of cationic yellow X-GL (CY) in aqueous solution on ATP/AC composites were studied. During all experiments, CY concentration was determined by UV-vis spectrophotometer. Research on the thermodynamic behavior indicated that the adsorption of CY obeyed the Langmuir isotherm model. The adsorption enthalpy was -16.37 kJ/mol, the Gibbs-free energy was -28.73 to -27.04 kJ/mol, and the entropy was about 35 J mol~(-1) K~(-1), which showed that the adsorption process was both exothermic and spontaneous. The kinetic parameters showed that absorption of CY on ATP/AC composites was best described by pseudo-second-order kinetics.