Removal of chromium(VI) ions from synthetic solutions by the fungus Penicillium canescens

R. Say1, N. Yilmaz2, A. Denizli3*

1 Department of Chemistry, Anadolu University, Eskisehir, Turkey
2 Department of Biology, Anadolu University, Eskisehir, Turkey
3 Department of Chemistry, Hacettepe University. Beytepe, Ankara, Turkey

Received 4 June 2002; accepted 3 January 2003


Penicillium canescens has demonstrated the ability to bind high amount of chromium(VI) from aqueous solutions. Cr(VI) adsorption capacity increases with the time during the first 4h and then levels off toward the equilibrium adsorption capacity. Biosorption of Cr(VI) ions reached equilibrium in 4h. Cr(VI) ions binding Penicillium canescens was clearly pH dependent. Cr(VI) loading capacity increased with increasing pH under acidic conditions, presumably as a function of Cr(VI) speciation and due to the H+ competition at same binding sites. The adsorption of Cr(VI) ions reached a plateau value at around pH 6.0. The maximum adsorption capacity of Cr(VI) ions onto the fungal biomass was 34.8mg/g. Elution of Cr(VI) ions was performed using 0.5M HCl. The fungus Penicillium canescens could be used for six cycles for biosorption.

Keywords: Cr(VI); Fungal biomass; Heavy metal-binding; Biosorption; Penicillium canescens

* Corresponding author
   E-mail : denizli@hacettepe.edu.tr