Biosorption of zinc ions from aqueous solution by the microalga Scenedesmus obliquus

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Monteiro, CM (Author) Other; Castro, PML (Author) Other; F. Xavier Malcata (Author) Other

Journal

Title: Environmental Chemistry Letters

Vol. 9

Pages: 169-176

ISSN: 1610-3653

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 35 Citations

Scopus - 54 Citations

Other information

Authenticus ID: P-002-R01

DOI: 10.1007/s10311-009-0258-2

Abstract (EN): Aquatic environments are often exposed to toxic heavy metals, which gain access to the food chain via microalgae and may cause severe problems at higher trophic levels. However, such a metabolic specificity can be taken advantage of in bioremediation strategies. The potential of a novel wild strain of Scenedesmus obliquus, previously isolated from a heavy metal-contaminated site in northern Portugal, to remove Zn from aqueous solutions was thus studied, using several initial concentrations. The removal extent reached its maximum by 1 day: 836.5 mg Zn/g biomass, at the initial concentration of 75 mg/L, mainly by adsorption onto the cell surface. Comparative studies encompassing a commercially available strain of the same microalgal species led to a maximum removal extent of only 429.6 mg Zn/g biomass, under identical conditions. Heat-inactivated cells permitted a maximum removal of 209.6 mg Zn/g biomass, at an initial concentration of 50 mg Zn/L. The maximum adsorption capacity of Zn, estimated via Langmuir's isotherm, was 330 mg Zn/g biomass. Finally, Zn removal was highest at pH 6.0-7.0. It was proven, for the first time, that such a wild microalga can uptake and adsorb Zn very efficiently, which unfolds a particularly good potential for bioremediation. Its performance is far better than similar (reference) species, especially near neutrality, and even following heat-treatment.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8