Original Articles: 2014 Vol: 6 Issue: 11
Removal of Pb (II) from aqueous solution by using Custard apple (Annona squamosa) bark powder: Kinetics and equilibrium studies
Abstract
A new adsorbent was prepared from Custard apple (Annona squamosa) and applied to remove Pb (II) ions from aqueous solution. The present studies were conducted in a batch adsorption process. The biosorbent was characterized by FTIR spectroscopy, scanning electron microscopic analysis, elemental analysis and X-ray diffraction analysis. The influence of PH, adsorbent dose, contact time, initial concentration of the adsorbate has been determined. The optimum pH for the removal of lead ions from aqueous medium is found to be pH=5. Kinetic parameters of adsorption such as Lagergren pseudo-first order, pseudo-second order and intraparticle diffusion model were determined. The sorption system follows pseudo-second-order kinetic model and equilibrium time is obtained after 50 min. The equilibrium data were analyzed by using Langmuir, Fruindlich and Dubinin- Radushkevich isotherm models. Langmuir model was fitted well by its good correlation co-efficient values. Desorption studies and recovery of adsorbent were carried out by using dil. HCl solution. The results suggested that the Annona squamoa bark powder can be used as effective, eco-friendly, low cost adsorbent in the removal of Pb (II) ions from aqueous solution.