Immobilization of Dithizone on Magnetic Zeolite in Less Toxic Medium and its Application as Adsorbent Cd(II) Ion in Water

Abstract

One of the most dangerous pollutants frequently found in environment are heavy metal ions. Industrial effluents especially those rich in heavy metals are potential pollution source for aquatic environment. In this study, magnetic modification of activated natural zeolite (MZ) was prepared and then used as host for immobilization of dithizone in less toxic alkaline medium. The obtained material, dithizone-immobilized magnetic zeolite (MZD) was applied as adsorbents for adsorption of heavy metal Cd (II) ion in water. The mechanism of interaction between the adsorbent and Cd (II) ion was studied by sequential desorption experiments of Cd (II) ion using different solvents. The adsorbents were characterized by FTIR and XRD to confirm the successful magnetization and immobilization of dithizone on the activated natural zeolite. Results of adsorption study shows that adsorption capacity of MZ and MZD adsorbents towards Cd (II) ion are 17.8 and 37.5 mg g-1, respectively. The adsorption of Cd (II) on both adsorbents is best described by pseudo 2nd order reaction and follow Langmuir isotherm adsorption model. Sequential desorption experiments has revealed that Cd (II) adsorption on MZ is dominated by electrostatic interaction while that on MZD is mostly occurred through complexation. The synthesized materials is promising to be used as adsorbent of heavy metals because it can magnetically be separated and selectively adsorbed heavy metals with higher capacity.