Structural properties and adsorption capability of activated carbon from oil palm shell by using hydrothermal-pyrolysis method

Activated carbon (AC) has a broad range of applications such as wastewater treatment, gas separation, purification, energy storage, and adsorbents. However, the majority of commercially activated carbons are made from nonrenewable fossil-based material. Therefore, biomass-derived activated carbon has attracted much attention in replacing fossil-based carbon precursors due to environmental issues. In this research, Oil palm shell (OPS), as one of local commodity by-products in Indonesian oil palm industry, was used as a raw material due to its high lignin content to produce high-yield AC to investigate the effect of different activator agents on the adsorption capability of materials. By varying the activator agents which are H3PO4 and ZnCl2, hydrothermal and pyrolysis method were conducted at 220°C for 8 hours and at 800°C for 1 hour, respectively. Raman spectroscopy, X-Ray Diffraction, and N2 Adsorption-Desorption measurements were used to characterize the structural properties of our ACs. The moisture content, ash content, volatile matter, and fixed carbon of the samples were tested and have met SNI standard 06-3730-1995 for technical activated carbon. The structural results indicate that our material has an amorphous structure with the dominance of microstructure pores while the highest surface area is owned by AC with an H3PO4 activator with a value of 859.52 m2/g. The adsorption capability of AC was tested through Methylene Blue and Rhodamine B adsorption which indicate that our materials have approached SNI standard and show good capability of adsoprtion. In general, this material can potentially be used for adsorbents to purify liquids in many applications especially to reduce color in wastewater treatments.