Activated Carbons from Palm Kernels Shells Prepared by Physical and Chemical Activation for Copper Removal from Aqueous Solution

Abstract

Abstract Preparation and evaluation of activated carbon from the palm kernel shell (PKS), an abundant agricultural residue, by physical and chemical activation were carried out. The activation treatment of adsorbent with and without chemicals modification was evaluated. The physical activation using nitrogen gas and chemical treatment using 10 wt.% of sodium hydroxide and nitrogen gas as the activating agent. This study evaluated the activation temperature and nitrogen gas rate. The results showed that activated carbon treated with NaOH followed by heating under nitrogen gas had the highest iodine number of 1062.8 mg/g and methylene-blue number of 247.2 mg/g (heating at 750 °C, nitrogen gas flow rate of 100 mL/min). The equilibrium data obtained at various initial concentration reasonably fit well with the Langmuir adsorption isotherm. The adsorption of Cu(II) ions fit with the Langmuir isotherm pattern with adsorption capacity (Xm) of 8.9445 mg/g and kf value of 0.16802 L/mg for activated carbon without NaOH treatment. The adsorption capacity of activated carbon with NaOH and heating at 750 °C under nitrogen gas was obtained 12.0773 mg/g and kf value of 0.15076 L/mg. Those results suggested the prepared adsorbent could be considered as a promising candidate for Cu(II) ions for wastewater treatment.