Equilibrium, kinetic and thermodynamic parameters of the biosorption of Ni2+ from aqueous solution by Streblus asper

被引：3

作者：

Adebayo, M.A. ^{[1
]}

Adediji, J.F. ^{[1
]}

Adebayo, A.A. ^{[2
]}

Adebayo, O.T. ^{[1
]}

机构：

[1] Department of Chemical Sciences, Ajayi Crowther University, Oyo, Oyo State, Nigeria

[2] Department of Chemistry, Catholic University of Rio de Janeiro-PUC-Rio, RJ, Brazil

来源：

Journal of Applied Sciences | 2012年 / 12卷 / 01期

关键词：

Adsorption - Adsorption isotherms - Biosorption - Free energy - Heavy metals - Ion exchange - Kinetic theory - Kinetics - Rate constants - Solutions;

D O I：

10.3923/jas.2012.71.77

中图分类号：

学科分类号：

摘要：

The biosorption of Ni2+ by Streblus asper, biomass was investigated in single metal solution. Batch kinetic studies were carried out in order to determine effect of adsorbent and adsorbate dose, pH of solution, agitation time and temperature on biosorption of Streblus asper. The maximum Ni2++ biosorption was obtained at pH 6.0. The equilibrium nature of Ni2++ biosorption was described by the Freundlich and Dubinin-Radushkevich isotherms. The value of n, the intensity of adsorption, is ≈2 indicating that Ni2++ is favourably biosorbed by Streblus asper. The saturation capacity, qm, of Ni2++ by Streblus asper was calculated to be 40.48 mg g-1. The value of the mean free energy of biosorption was calculated to be 4082.48 kJ mol-1 which indicates that the biosorption may occur via a chemical ion-exchange mechanism. The results of the thermodynamic investigations indicated that the adsorption reactions were spontaneous (ΔG0) and irreversible (ΔS>0). The pseudo second-order kinetic model was used to analyse the kinetic data. The second order rate constants for the biosorption of Ni2++ from solutions by Streblus asper was evaluated to be 1.35 g mg-1 min-1. © 2012 Asian Network for Scientific Information.

引用

页码：71 / 77