Adsorption of acetic acid onto activated carbons produced from hazelnut shell, orange peel, and melon seeds

Abstract

In this study, hazelnut shells, orange peel, and melon seeds were selected as raw materials in the preparation of activated carbon. Various activators at different concentrations under two activation temperatures of 300 °C and 500 °C were utilized. All produced adsorbents and a commercial activated carbon as a reference were used for the adsorption of acetic acid from its aqueous solutions in the various initial concentrations. The effect of the amounts of adsorbents was also studied. Removal efficiencies (Re%) and adsorption capacities (Qe) were experimentally determined. Langmuir, Freundlich, and Temkin isotherms were modelled, and their parameters were calculated. The surface area, pore volumes, and average pore width of the activated carbons were characterized by N2 adsorption at 77.35 K using the BET, t-plot, and BJH methods, respectively. The highest BET surface area of the activated carbon from hazelnut shells was obtained as 717.738 m2/g at 500 °C activation temperature and 60% H3PO4 concentration. SEM images and FTIR analyses were investigated. It was found that activated carbons of hazelnut shells and orange peel showed higher efficiencies than commercial activated carbon.