Adsorption of Malachite Green Dye Using Modified γ-Alumina

Modified γ-Alumina was used for the adsorption of the cationic dye malachite green (MG) from aqueous solutions. The properties of the modified particles were initially determined by FT-IR, XRD, SEM, and EDAX. The effects of such parameters as initial dye concentration, contact time, initial pH, adsorbent dose, and temperature on dye removal were investigated and the pHzpc of the adsorbent was determined. Results showed that equilibrium was achieved in 60 min and MG removal increased with increasing adsorbent dosage and pH. The experimental results indicated that 0.1g of modified γ-Alumina was capable of removing 91.61% of the MG dye from an initial concentration of 50 mg L-1 at pH=10. Results of isotherm and kinetic studies revealed that adsorption of Malachite Green dye onto modified γ-Alumina best fitted the Temkin isotherm and pseudo-second-order kinetic models.