Evaluation of chemically activated carbon from Leucaena leucocephala biomass for cadmium adsorption

Water contamination caused by heavy metals is a common problem in industrialisation. There are many factors that cause this to happen and many ways to overcome it. One of the way is activated carbon which is one of the adsorbents that can eliminate heavy metals. The objective of this study is to evaluate the heavy metals uptake from contaminated water using activated carbon made from Leucaena leucocephala biomass. Leucaena Leucocephala is also known as Petai Belalang wood, which is a fast growing species. By using this abundant species for producing activated carbon it could be an advantages for economic and environmental perspectives. Activated carbon of Leucaena leucocephala biomass was produced by chemical activation at impregnation ratios NaOH:charoal (w/w) of 1:1, 2:1 and 3:1. Activated carbon was prepared under activation temperature 700, 750 and 800 oC. Thermogravimetric analysis was conducted at heating rate temperature from 30 oC to 900 oC. Adsorption of cadmium contained in sample was measured with Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) at specific wavelength. Scanning Electron Microscope (SEM) was used to analyse the surface morphology and BET analysis was conducted for pore structure characteristic. Batch adsorption was studied in different contact time, initial concentration, solution pH and temperature. Overall results for batch adsorption study show that the activation temperature 800 oC with 3:1 ratio gives higher result for adsorption rate which is 99.9748 %. For the surface area, activation temperature 800 oC with 3:1 ratio also gives a higher surface area which is 776 m2g-1. Therefore, the adsorption percentage and the surface area are improved with the increased of activation temperature and the chemical ratio. Based on the finding Leucaena Leucocephala has the potential to be used as a raw material to produce activated carbon at a low production cost.