Adsorption Performance for the Removal of Cu(II) on the Ammonium Acetate Modified Sugarcane Bagasse

Sugarcane bagasse, an agricultural waste biomass was innovatively used to prepare ammonium acetate modified sugarcane bagasse via a simple wet impregnation method. The prepared adsorbent was used for the adsorptive removal of copper from aqueous solution. It was found that an increase in adsorbent dosage significantly increased the removal efficiency for copper. Compared to the raw bagasse, the adsorption capacity of the modified bagasse was dramatically enhanced by 116.2%. At pH 5.0, 7.0 and 9.0, the reaction kinetic data were simulated and compared using pseudo-first-order, pseudo-second-order and Elovich kinetic models. Results indicate that both pseudo-second-order and Elovich kinetic models could better describe the adsorption kinetics. This demonstrates that the adsorption of copper onto the modified bagasse was a chemisorption process in which the ratedetermining step is diffusion in nature. Thermodynamic analysis demonstrated the enthalpy and entropy of the adsorption process as 643.6 KJ mol^-1 and 250.5 J mol^-1 k^-1, respectively. The positive value of the reaction enthalpy implies that the uptake of copper increases with a rise in the reaction temperature. The adsorption of copper was spontaneous and endothermic in nature.