Removal of copper from aqueous solutions using sawdust, zeolite and activated carbon: Equilibrium time convergence

Abstract

In this study, adsorption of copper(II) ions from aqueous solutions on sawdust, zeolite and activated carbon was studied using batch experiment techniques. The effect of different parameters such as pH of solution, adsorption time and amount of adsorbents were evaluated. Favourable pH for maximum copper adsorption was 6, 6 and 4 for sawdust, zeolite and activated carbon, respectively. The equilibrium of copper adsorption has been described by the Langmuir, Freundlich and Temkin isotherms and their fitness for adsorption was compared. The Temkin model had a better fitness than the other models. Maximum adsorption capacity of sawdust, zeolite and activated carbon were 96.11%, 96.2% and 97.02% (mg/g), respectively. The study of applicability of kinetic models of Lagergren (1898) and Ho et aL (1996) showed the latter model to be better fit than the former. The rates of adsorption obey the rules of A-order model with good correlation.