Home About us MoEF Contact us Sitemap Tamil Website  
About Envis
Whats New
Microorganisms
Research on Microbes
Database
Bibliography
Publications
Library
E-Resources
Microbiology Experts
Events
Online Submission
Access Statistics

Site Visitors

blog tracking


 
Separation Science and Technology
Vol.,
49, No. 3, 2014; Pages: 376-387

Removal of Zinc from Aqueous Solution by Metal Resistant Symbiotic Bacterium Mesorhizobium amorphae

Xiuli Hao, Osama Abdalla Mohamad, Pin Xie, Christopher Rensing & Gehong Wei

College of Life Sciences, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A & F University , Yangling , Shaanxi , China.

Abstract

Biosorption of zinc by living biomasses of metal resistant symbiotic bacterium Mesorhizobium amorphae CCNWGS0123 was investigated under optimal conditions at pH 5.0, initial metalconcentrations of 100 mg L-1, and a dose of 1.0 g L-1M. amorphae exhibited an efficient removal of Zn2+ from aqueous solution with maximum biosorption capacity of 120.85 mg g-1. Moreover, more than 70% Zn2+ could be recovered from Zn-loaded biomass at pH 1.0. Both the Langmuir and Freundlich isotherms provided a better fit to experimental data for Zn2+ sorption with correlation coefficients of 0.9885. Kinetics models suggested there was more than one step involved in the Zn2+ sorption process, while a pseudo-second-order model was more suitable to describe the kinetic behavior accurately, indicating a chemisorption process. Carbonyl, amino, carboxyl, and aromatic groups were responsible for the biosorption of Zn2+ by M. amorphae. Cellular deformation, precipitate, and damage were found after Zn2+ treatment. Competitive sorption revealed Cu2+, Cd2+, and Ni2+ were competed with Zn2+ for adsorption sites with the order: Cu2+ > Cd2+ >> Ni2+.

Keywords:


 
 
Copyright © 2005 ENVIS Centre ! All rights reserved
This site is optimized for 1024 x 768 screen resolution