Biosorption of inorganic and methyl mercury by a biosorbent from Aspergillus niger

• Published in: World journal of microbiology & biotechnology 2003-04, Vol.19 (3), p.291-295
• Main Authors: KARUNASAGAR, D, ARUNACHALAM, J, RASHMI, K, NAVEENA LAVANYA LATHA, J, MARUTHI MOHAN, P
• Format: Article
• Language: English
• Subjects: Aqueous solutions; Bacteria; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Ions; Mercury; Methylmercury; Sorption; Water analysis; Water sampling
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1023/A:1023610425758

A biosorbent prepared by alkaline extraction of Aspergillus niger biomass was evaluated for its potential to remove mercury species - inorganic (Hg^sup 2+^) and methyl mercury (CH^sub 3^Hg^sup +^) - from aqueous solutions. Batch experiments were carried out to determine the pH and time profile of sorption for both species in the pH range 2-7. The Hg^sup 2+^ exhibited more rapid sorption and higher capacity than the CH^sub 3^Hg^sup +^. Further, removal of both mercury species from spiked ground water samples was efficient and not influenced by other ions. Sorption studies with esterified biosorbent indicated loss of binding of both mercury species (>80%), which was regained when the ester groups were removed by alkaline hydrolysis, suggesting the involvement of carboxyl groups in binding. Further, no interconversion of sorbed species occurred on the biomass. The biosorbent was reusable up to six cycles without serious loss of binding capacity. Our results suggest that the biosorbent from Aspergillus niger can be used for removal of mercury and methyl mercury ions from polluted aqueous effluents.[PUBLICATION ABSTRACT]