Characterization of Acid Treated Activated Carbon from Oil Palm Empty Fruit Bunches (EFB)

Abstract

Activated carbon (AC) has a high potential to act as dispersing agent as the surface of the activated carbon can be modified by chemical and/or physical treatments. In this work, several acid treatment methods have been conducted by using nitric acid (HNO3), hydrogen peroxide (H2O2) and a mixture of nitric acid and sulfuric acid To functionalize the activated carbon from oil palm empty fruit bunches (AC-EFB), those treatments were followed by washing with distilled water until neutral pH and dried overnight in an oven at 80 °C. A dispersion test was conducted by dispersing a small amount of the treated AC-EFB in distilled water using a sonicator for 5 minutes. The modified AC-EFB has been characterized by using, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. Based on observation, the treated AC-EFB with a mixture of acids has a stable suspension compared to other methods which indicate the presence of a hydroxyl group attached to the surface of AC-EFB. FTIR results further confirmed the presence of the functional group of hydroxyl. The SEM micrograph shows the formation of unique microstructure on the AC-EFB structure after treated with method M3 whereas the number of pores developed was increased. The atomic percentage of oxygen of treated AC-EFB was higher than untreated AC-EFB, which indicates the hydroxyl group was attached to the surface of activated carbon as proven by EDX analysis. Thus, acid treated method using HNO3/H2SO4 mixture shows a promising approach on synthesizing the activated carbon with unique properties and characteristics.