Application of Groundnut Shell in Natural and Carbonized forms as Adsorbent for the removal of 2,4,6-trichlorobenzoic acid from Aqueous Systems

Abstract

In this study, the suitability of groundnut shell (GS) both in the natural (UGS) and carbonized (MGS) forms as adsorbent for 2,4,6-Trichlorobenzoic Acid (2,4,6-TCB) was investigated through batch equilibration. While the kinetics of the adsorption process follow the pseudo-second-order kinetics, the intra-particle diffusion model suggests that the molecules of UGS are more aggregated particularly at lower concentrations in aqueous solution than those of MGS. The isotherms of 2,4,6-TCB on GS seemed close to linear (R2 > 0.993) with the organic carbon normalized partition coefficient (Koc) being several folds higher in MGS under the experimental conditions. The removal efficiency of 2,4,6-TCB was better enhanced at lower pH. In this study, carbonization significantly improved the surface area and adsorption capacity of GS. Results indicated that GS derived from agricultural wastes, particularly in carbonized form, can play an important role in the removal of hydrophobic organic chemicals such as 2,4,6-TCB from aqueous systems.