Surface functionalized carbon microspheres for the recovery of copper ion from refinery wastewater

Abstract

Micro-sized carbon spheres (CNS) were synthesized by hydrothermal process from glucose solution at 443.15 K and two different reaction times. The synthesized CNS samples were surface functionalized with hydroxyl (-OH) functional groups using NaOH treatment, and were tested in batch adsorption to remove heavy metal ion (Cu2+) from aqueous solutions. Experimental results revealed that CNS contains mostly amorphous carbon. NaOH functionalized CNS had significantly higher adsorption capacity of copper ∼170×10−3 Kg Cu2+/Kg-CNS as compared to the untreated CNS. The adsorption isotherms were well fitted by the Langmuir isotherm equation. The surface morphology of the native and functionalized CNS samples was characterized by a number of techniques and based on which the adsorption of copper ion was discussed.