Preparation of Activated Carbon Adsorbent From Coconut Husk for the Adsorption of Lead (Ii) Ions From Aqueous Solution

Abstract

Heavy metals contamination of water and wastewater is a common phenomenon. Industrial wastewaters are usually the cause of heavy metals pollution of the environment. In this work, the adsorptive removal of lead metal ions in aqueous solution is investigated using an activated carbon derived from coconut husk. The activated carbon was modified with NaOH and characterized for functional group, micro-structure and textural properties. The activated carbons have a surface area of 304.38 m 2 /g from 600 °C activation with NaOH modification and 281.19 m 2 /g (300 °C) without modification. FTIR demonstrated the different functional groups present and the SEM images showed the pores on the surface of the activated carbon due to the NaOH modification. The maximum adsorption capacity of 91.70 and 73.90 mg/g were obtained for the coconut husk modified and unmodified adsorbents respectively. The adsorption kinetics for lead metal ions onto both adsorbents can be described by a pseudo-second-order rate model and are well fitted to the Langmuir adsorption isotherm. The results indicated that coconut husk in modified and unmodified forms can be used for the efficient removal of lead (II) ions from water and wastewater.