Abstract

An alomina-based nano adsorbent was prepared by modification of the external surface of γ-alumina (γ-Al 2 O 3 ) nanoparticles with functional groups of a new Schiff base 4-(2-hydroxy-3-methoxy-benzylidene)- amino-5-methyl-2,4-dihydro-1,2.4triazole-3-thione "L". In order to the removal of Cr(VI) from aqueous solutions, we used the reaction of the sodium dodecyl sulfate coated nano-alumina with L solution for. This new modifying strategy significantly improve removal efficiency due to facilitate the accessibility of Cr ions to the activated sits. The surface morphology and chemistry of the adsorbent was characterized by SEM and FT-IR spectroscopy, respectively. Effect of most important parameters such as effect of pH value, contact time, adsorbent dosage, and initial Cr(VI) concentration on removal efficiency were investigated. In order to interpret the results Langmuir and Freundlich isotherm models were used. The results show that prepared absorbent significantly remove heavy metal ions from wastewater. © 2018 University of Kashan.