Heavy Metals Adsorption on Cyanex-272 Modified Activated Carbon: Efficacy and Selectivity

Abstract

This study investigated the potential use of activated carbon functionalized with Cyanex272 (AC-Cyanex 272), in the removal of lead, copper and zinc cations from aqueous solutions. The modified adsorbent was characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Zeta-Meter and particle size distribution. Batch adsorption experiments were performed as a function of pH, contact time, and initial metal ion concentration. Adsorption was found dependent on these parameters. The adsorption capacities were very high (126.36, 175.5 and 157.16 mg g^-1 for Pb²⁺, Cu²⁺ and Zn²⁺ respectively). Langmuir and Freundlich isotherms were used as models for the equilibrium adsorption data and adsorption kinetic data are best described by the second order model.