Evaluation of alkaline-based activated carbon from Leucaena Leucocephala produced at different activation temperatures for cadmium adsorption

Abstract

Heavy metal contamination in water is happening worldwide. Adsorption using activated carbon is a common choice for cleaning the wastewater. The drawback of activated carbon is the higher cost of production due to the need for high heat in the process. This work investigated on activated carbon produced from the abundantly available Leucaena leucocephala biomass in order to reduce the cost of raw material. The biomass was chemically activated at different activation temperatures. The produced activated carbon was characterized using SEM, FT-IR, surface analyzer, and TGA. Isothermic and thermodynamic studies were done to evaluate the adsorption properties of the activated carbon. It was found out that higher surface area can be obtained using the higher activation temperature. Higher NaOH to carbonized sample ratios also resulted in higher surface area for all activation temperatures, which are 662 m(2)g(-1) for 700 degrees C activation temperature, 735 m(2)g(-1) for 750 degrees C, and 776 m(2)g(-1) for 800 degrees C. Isothermic studies showed that all of the activated carbon that is produced from Leucaena leucocephala biomass are fit to the Langmuir isotherm, regardless of any activation temperature. Lastly, the thermodynamic study found out the adsorption process is endothermic, reflected by the positive value of Delta H-o. It can be concluded that Leucaena leucocephala is a promising alternative material for producing activated carbon.