Modification of Activated Carbon Prepared From Pigeon Pea Husks with Eriochrome Black T for Removal of Copper (II) Ions

Abstract

Wastewater pollution due to heavy metals is one of the most important problems facing humanity today. The current study showed a sensitive and effective method for removal of copper (Cu) from aqueous solutions using activated carbon (AC) modified with Eriochrome Black T (EBT). The AC was prepared from pigeon pea husks, since this is an abundant and inexpensive natural resource, using chemical activation with phosphoric acid solution (70%), then physically modified with EBT. Surface properties of the AC-EBT phase were characterised by scanning electron microscopy (SEM) analysis and Fourier transmission infrared (FT-IR) spectroscopy. The high adsorption of AC-EBT is due to the well-developed pores on the fabricated AC-EBT, which lead to high Cu uptake, and the maximum monolayer adsorption capacity of 158.73 mg g-1 after 1 hour contact time. The experimental data fitted well to the Langmuir adsorption isotherm. Results demonstrated that AC-EBT would be a useful and valuable method for controlling water polluted with copper ions. Index Terms-Activated carbon; Copper ion; Eriochrome Black T; Pigeon pea husks.