Adsorption study on the removal of Cu (II) ions from aqueous solution using melon (Citrus cocolynthus) husk as a biosorbent in a fixed bed column. Nigerian Research Journal of Engineering and Environmental Sciences 3 (1) pp. 103-117

Abstract

Adsorption potentials of melon husk for the removal of copper (II) ions from an aqueous solution in a fixed bed column were investigated. Melon husk was prepared and characterized based on functional groups and morphology using Fourier Transform Infra-Red (FTIR) spectrum and Scanning Electron Microscope (SEM) imaging respectively. Fixed bed column study was carried out as a function of simulated effluent flow rate (0.5-1.5 ml/min), initial Cu (II) concentration (5-20 mg/l), and bed height (6-12 cm). The dynamics of the bed were correlated using kinetics isotherms, Adams-Bohart, Bed Depth Service Time (BDST), and Yoon Nelson models. The SEM morphology indicated the adsorbent’s high surface roughness that is evenly dispersed before adsorption and lower adsorbent porosity after adsorption. FTIR spectrum of the adsorbent before and after adsorption showed peaks with slight shifts in the position of carboxylic (1682.92-1670.91 cm-1) and amine (1615.86-1560.15 cm- 1) groups attributed to the attachment of Cu (II) ions via functional groups. The BDST model gave the best agreement between the experimental and the model prediction with R2 = 0.991. High metal removal (87.5-100%) was achieved within the range of chosen variables. The column performance indicated the efficiency of the melon husk as an adsorbent for Cu (II) which can be utilised in wastewater treatment