Evaluation of the Effectiveness of Low Cost Adsorbents from Oil Palm Wastes for Wastewater Treatment

Abstract

In the present research, oil palm wastes such as palm kernel shell (PKS), empty fruit bunch (EFB) and palm oil sludge (POS) were converted into biochars through pyrolysis. The charred products of PKS (CPKS), EFB (CEFB) and POS (CPOS) were tested for batch adsorption of copper (Cu2+), lead (Pb2+) and cadmium (Cd2+). Their adsorption performances were compared with the respective un-charred form, i.e. the biosorbents. The adsorption equilibrium was evaluated by varying initial metal concentration. Experimental data were analysed by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models. It was found that for Cu2+ removal byPOS and Pb2+ removal by CPOS, the equilibria were best represented by Langmuir model exhibiting the smallest sum of normalised error (SNE). For Cd2+ adsorption onto POS, the equilibrium was best fitted by Freundlich model with the lowest value of SNE.