Adsorption of iron(III) from aqueous solution onto activated carbon of a natural source: Bombax ceiba fruit shell

Abstract

Under this study, the extent of Fe(III) adsorption from aqueous solution onto activated charcoal prepared from a natural source, Bombax ceiba fruit shell was investigated. The fruit shell was carbonized and then activated using zinc chloride (ZnCl2) as an activating agent. The prepared activated carbon was characterized using Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS) and Point Zero Charge (PZC). Some important parameters influencing the adsorption rate namely adsorbent dosage, initial metal ion concentration, contact time and solution pH were optimized through batch adsorption study. The optimum adsorption was found to be at pH 3.5, adsorbent dosage 0.05 g, contact time 25 min and initial Fe(III) concentration 75 mg/L. Langmuir, Freundlich and Temkin isotherm models were investigated. Where, Temkin model was found to be more suitable compared to other two describing the adsorption of Fe(III). The maximum iron(III) removal efficiency was commenced to be 99.10 % and the adsorption capacity of the prepared activated carbon was initiated as 37.16 mg/g.