Basic dye removal from synthetic wastewater by adsorption on palm ash

Abstract

Palm ash, an agriculture waste residue from palm oil industry in Malaysia, was investigated as a replacement for the current expensive activated carbon adsorbent for removing of basic blue 66 dye from synthetic wastewater. Adsorption equilibrium and kinetics of basic dye from aqueous solutions onto palm oil were studied in a batch system. Effects of the initial concentration (50 to 600 mg/l), contact time, pH (2-12) and temperature on adsorption rate were investigated. The experimental data were analyzed by the Langmuir, Freundlich and Redlich-Peterson models of adsorption. Equilibrium data fitted well Langmuir, Freundlich and Redlich-Peterson models in the range of 50-600 mg/l. The kinetic models pseudo firstorder and pseudo-second-order were tested to investigate the adsorption mechanisms. It was shown that second-order kinetic equation could best describe the adsorption kinetics. The results indicate that the activated palm ash could be employed as a low cost alternative to commercial activated carbon.