Biodegradation and biosorption of acid anthraquinone dye

The acid anthraquinone dye Tectilon Blue (TB4R) is a major coloured compone nt from the aqueous effluent of a carpet printing plant in Northern Ireland . The aerobic biodegradation of TB4R has been investigated experimentally i n batch systems, using three strains of bacteria, namely, Bacillus gordonae (NCIMB 12553), Bacillus benzeovorans (NCIMB 12555) and Pseudomonas putida (NCIMB 9776). All three strains successfully decolourised the dye, and resu lts were correlated using Michaelis-Menten kinetic theory. A recalculation of the reaction rate constants, to account for biosorption, gave an accurat e simulation of the colour removal over a 24-h period. Up to 19% of the dec olorisation was found to be caused by biosorption of the dye onto the bioma ss, with the majority of the decolorisation caused by utilisation of the dy e by the bacteria. The reaction rate was found to be intermediate between z ero and first order at dye concentrations of 200-1000 mg/l. (C) 2000 Elsevi er Science Ltd. All rights reserved.