Activated Carbon Based on Borassus aethiopum Shells, Hulls, Kernels and Fruits for Removal of Phenol and 2-Chlorophenol from Water

Abstract

This study aimed at developing activated carbons from Borassus aethiopum shells (BaS), hulls (BaH), kernels (BaK) and fruits (BaF) for removing phenol (Ph) and 2-chlorophenol (2-CP) from aqueous solution. The preparation of the activated carbons involved carbonization of the starting materials at 500 ºC followed by chemical activation at 600 ºC using 0.5 M H₃PO₄ acid. The prepared activated carbons were found to be mesoporous having pore sizes and surface areas in the range of 3.2 to 3.5 nm and 644 to 740 m²/g, respectively. Thermogravimetric analysis (TGA) thermograms showed that the prepared activated carbons can be applied in the batch solution with a temperature not greater than 500 ºC as above this temperature, the materials decompose. Adsorption experiments showed that the uptake of 100 mg/L of Ph and 2-CP from water is favourable using an adsorbent dose of 0.5 g and a contact time of 6 hours. On the other hand, the batch solution of pH 8 and 6 favoured the adsorption of Ph and 2-CP, respectively. Moreover, the adsorption of the aforementioned adsorbates strongly depended on their initial concentrations and temperature of the batch solution. Equilibrium adsorption isotherms fitted into both Langmuir and Freundlich isotherms, but the Freundlich adsorption model was found to have the highest regression value, hence the best fit.