Journal of Hazardous Materials, Vol.152, No.3, 1256-1267, 2008
High adsorption capacity NaOH-activated carbon for dye removal from aqueous solution
In this study, the surface coverage ratio (S-c/S-p) and monolayer cover adsorption amount per unit surface area (q(mon)/S-p) were employed to investigate the adsorption isotherm equilibrium of the adsorption of dyes (AB74, BB1 and MB) on NaOH-activated carbons (FWNa2, FWNa3 and FWNa4); the adsorption rate of the Elovich equation (1/b) and the ratio of 1 min adsorption amount of adsorbate to the monolayer cover amount of adsorbate (q(1)/q(mon)) were employed to investigate adsorption kinetics. The q(m)/S-p of NaOH-activated carbons was better than that of KOH-activated carbons prepared from the same raw material (fir wood). The S-c/S-p values of the adsorption of all adsorbates on adsorbent FWNa3 in this study were found to be higher than those in related literature. Parameters 1/b and q(1) of the adsorption of dyes on activated carbons in this study were higher than those on KOH-activated carbons; the q(1)/q(mon) value of FWNa3 was the highest. The pore structure and the TPD measurement of the surface oxide groups were employed to explain the superior adsorption performance of FWNa3. A high surface activated carbon (FWNa3) with excellent adsorption performance on dyes with relation to adsorption isotherm equilibrium and kinetics was obtained in this study. Several adsorption data processing methods were employed to describe the adsorption performance. (c) 2007 Publishad by Elsevier B.V