Application of Kenaf Bast Fiber to Adsorb Cu(II), Pb(II) and Zn(II) in Aqueous Solution: Single- and Multi-metal Systems

Abstract

Improper discharge of heavy metals such as cadmium, copper, nickel, lead and zinc to the environment could impose severe health and toxicological problems. Within Malaysian context, Cu(II), Pb(II) and Zn(II) are the most common heavy metals present in various industrial wastewater effluents. The removal of Cu(II), Pb(II) and Zn(II) from water bodies is of interest due to their high toxicity. Copper and lead are classified as carcinogenic agents. Accumulation of zinc in human and animal increases the risk of blood, nervous and reproductive disorders. In this study, the ability of Kenaf Bast fiber (KBF) adsorbent to sequester Cu(II), Pb(II) and Zn(II) from synthetic solution with respect to solution pH, initial metal concentration and adsorbent dosage was investigated. Both single-metal and multi-metal system studies were carried out in batch experiments. The adsorption equilibrium was analyzed by Langmuir and Freundlich isotherm models. The biomass adsorbent was characterized using Scanning Electron Microscope (SEM), Energy Dispersive X-ray spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). The optimum conditions of metals adsorption was found at pH 4.0 (Pb(II)) and pH 5.0 for both Cu(II), and Zn(II). The maximum adsorption capacity estimated using Langmuir isotherm model was in the order of Pb(II) (50.0 mg/g) > Cu(II) (33.56 mg/g) > Zn(II) (13.68). The analysis of SEM, EDX and FTIR proved metal ions uptake by the adsorbent. The result highlights the significance of KBF as effective natural adsorbent for Cu(II), Pb(II) and Zn(II) removal from water bodies.