Muhandisī-i Bihdāsht-i Muḥīṭ (Jun 2015)
Survey Removal Efficiency of Cadmium from Aqueous Solutions Using Commercial Aluminum nano oxide: Kinetic Study of the Equilibrium
Abstract
Background: Human activities often diffuse heavy metal to the environment, which bring hazards up for human health when the concentration of these metals reaches high levels. The purpose of this study is evaluation effect of aluminum oxide Nano particles on cadmium removal from aquatic environment. Methods: This is a fundamental applied study which has been performed in order to investigation cadmium removal by using gamma aluminum nano oxide commercially prepared. In present study effects of pH, nano aluminum oxide concentration, initial concentration of cadmium, and contact time on kinetics and adsorption isotherm of cadmium by gamma Nano aluminum oxide were studied. Results: The results of experiments showed that cadmium ion had maximum adsorption over nano aluminum oxide on pH=3. Also by increasing adsorbent dose, adsorption efficiency was increased as by addition nano aluminum oxide from 0.5 g up to 4 g, the adsorption efficiency reached to 33%. By increasing cadmium initial concentration from 5 to 10 mg, removal efficiency was decreased from 29% to 25%. However the best time for adsorption was obtained at 60 minutes and the remaining time had no more effect on the removal efficiency. Data related to isotherm test for nano aluminum oxide has more conformity with Freundlich isotherm model (R2=0.9998). The results of cadmium adsorption kinetic showed that nano aluminum oxide has followed second order kinetic model (R2=0.9879). Conclusion: Nano Gamma-aluminum oxide adsorbent can introduce as an adsorbent for removal of cadmium from aquatic environment.
