Adsorptive Removal of Ni2+ from Aqueous Solution by Low Cost Cellulosic Adsorbent-Adsorption Kinetics and Isotherm Study

Abstract

Abstract Adsorptive removal of Ni2+ from aqueous solution by low cost cellulosic adsorbent was investigated with respect to adsorption kinetics and adsorption isotherm. Adsorbent was characterized by BET surface area, SEM, EDX, FTIR and Zeta potential technique and reported earlier. The surfaces contain carbonyl and hydroxyl functional groups, which act as binding sites for Ni2+ ion. Adsorption kinetics of Ni2+ was tested by first order, Elovich, parabolic diffusion and Bangham kinetic equations. Thermodynamic parameters like ΔH ≠, ΔS ≠ and ΔG ≠ were calculated from the kinetic data. The rate of adsorption was high at high adsorption temperature. Positive values of ΔS ≠ reflect some structural exchange among the active site of the adsorbent and metal ion. Freundlich, Langmuir, Temkin isotherms and distribution coefficient were found fit to the adsorption isotherm data.