Adsorption of copper(II) on dithizone-immobilized coal fly ash

The adsorption of Cu(II) ions onto selective adsorbent of coal fly ash from Sugar Factory Madukismo, Yogyakarta, Indonesia modified with dithizone has been investigated in batch mode. Some parameters influencing immobilization of dithizone and adsorption of Cu(II) were optimized including an effect of pH, contact time and initial concentration of Cu(II) ions. The FT-IR and XRD analytical results show that the surface of coal fly ash can be modified by immobilization of selective organic ligand towards Cu(II) ions. The optimum conditions for adsorption of Cu(II) are achieved at pH 5, the optimum mass of DICFA and ACFA for copper adsorption were 0.2 g. Kinetics adsorption for copper ions follows pseudo-second-order kinetics with optimum adsorption contact time 60 min for DICFA and ACFA. Isotherms adsorption for Cu ion follow the Langmuir isotherms with chemisorption process and optimum concentration of Cu ion adsorption of 70 mg L-1 for DICFA and ACFA. © 2020 Trans Tech Publications Ltd, Switzerland.