Removal of azo dye from aqueous solution by a new biosorbent prepared with Aspergillus nidulans cultured in tobacco wastewater

A new biosorbent was prepared from the dead biomass of fungus Aspergillus nidulans G, which was capable of utilizing tobacco wastewater (TWW) as a sole substrate. The characterization of the biosorbent surfaces, biosorption kinetics, isotherm models and the effects of various experimental factors were investigated. The kinetics and equilibrium biosorption were well-described by pseudo-second-order kinetic and Langmuir isotherm model, respectively. According to the Langmuir model, the maximum biosorption capacity of Congo red (CR) was 357.14 mg/g at 30 degrees C and pH 6.8, which competed well with other biosorbents reported. The results suggested that this low-cost, environmentally friendly and efficient biosorbent may be useful for the removal of azo dyes from aqueous solution. (C) 2013 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.