Kinetic and equilibrium studies on the selective removal of heavy metal by Neem seed and husks using column adsorption studies

摘要

The activated carbon were produced from neem (Azadirachta Indica) husk and seed and activated with ZnCl2 and H3PO4. The prepared adsorbents were used to adsorb heavy metals (Cd, Cr, Ni, Zn and Pb) in a multi-component system. The extent of adsorption of the metals were in this order; Cr (82%), Pb (70%), Ni (61%), Zn (59%) and Cd (36%). The kinetics study was studied using Pseudo-second-order rate model and Weber-Morris Intraparticle Diffusion Model (WMIDM) while the adsorption isotherms were studied using Langmuir and Freundlich Adsorption Isotherm. The adsorption isotherms best fit the Langmuir Adsorption Isotherm relative to the Freundlich Isotherm.