BatchHeavy MetalsBiosorption by Punica granatum Peels: Equilibrium andKinetic Studies

Abstract

This research was conducted to study the feasibility of using fruit peels as biosorbent for removal of Pb⁺², Cu⁺² and Zn⁺² ions from simulated wastewater. A waste biomass of Pomegranate Peel or Punicagranatum L. (P. granatum L.) was chosen as neutral biosorbent in this study.Fourier transformation infrared (FTIR) was used to characterize the surface of PGP, the results confirm that amino, carboxylic, hydroxyl and carbonyl group on the surface of PGP. Different parameters such as initial concentration range between (25-200) mg/L, pH (3-7), contact time (1-2) hour, amount of sorbent (0.1- 4) gm, agitation speed range (200- 500) rpm and temperature (25- 50^oC), influencing the sorptive process were examined. Sorption equilibrium isotherm and kinetic data fit well by the Langmuir isotherm and the pseudo-second-order kinetic model, respectively. Sorption processes were spontaneous and exothermic in nature according to the thermodynamic results and the equilibrium was attained within 60 minute. The amount of sorbed metal ions was calculated as 9.9, 9.5 and 7.75 mg/g dry PGP for Pb⁺², Cu⁺² and Zn⁺²ions, respectively, at pH 5; temperature 25^oC; contact time 1hr and 4 gm of peels.