The presented study investigated the characteristics and mechanism of zinc-ion containing wastewater treated by Granular Activated Carbon (GAC). GAC was pretreated by HCl with different concentrations to evaluate the influence of HCl on the specific s...
The presented study investigated the characteristics and mechanism of zinc-ion containing wastewater treated by Granular Activated Carbon (GAC). GAC was pretreated by HCl with different concentrations to evaluate the influence of HCl on the specific surface area of GAC. Batch adsorption experiments were conducted to study the effects of pH, contact time, adsorbent dosage, co-existing ions, complexing agents and temperature. Kinetic studies revealed that the process of zinc-ion containing waste water treated by activated carbon is in confidence limits of both pseudo-first-order and pseudo-second-order model. The equilibrium data of zinc-ion containing waste water treated by activated carbon was fitted in Freundlich and Langmuir isotherm model and the R2 indicated that the Langmuir model fit better. The maximum monolayer adsorption capacity of zinc was 5.17 mg/g at an optimum pH 7. The Arrhenius activation energy for the adsorption of zinc onto GAC was 10.97 kJ/mol. The adsorption of zinc-ion was affected by Cu2+ more significantly. The adsorption capacity of zinc-ion by GAC was highly influenced by the existence of Nitrilotriacetic Acid (NTA).