KINETIC, THERMODYNAMIC AND ISOTHERM STUDIES OF ADSORPTION OF CIBACRON RED C-2G USING PEANUT SHELL PRETREATED WITH HYDROCHLORIC ACID

The kinetics, thermodynamics, and isotherm studies of the adsorption of Cibacron red C-2G (a reactive dye) by peanut shell was performed by batch adsorption method. The kinetics of the adsorption obeyed best the pseudo-second order model with high correlation coefficients between 0.998 and 0.999 for the initial dye concentrations between 10 mg/L and 150 mg/L. From thermodynamic studies, the adsorption was of spontaneous nature. Standard enthalpy and entropy changes of the adsorption were positive. Adsorption isotherm obeyed the Freundlich model. While the amounts of dye removed by peanut shell were increasing with increasing contact time, initial dye concentration and solution temperature, it decreased with increasing pH. Maximum percent adsorption was determined to be between 85.64 and 91.98% under all the experimental conditions. It was concluded that the peanut shell pretreated with hydrochloric acid would be used as a cheap adsorbent as an alternative to activated carbon for the removal of undesired dyes pollution.