Reactive azo dyes occur in textile dyehouse wastewater in concentrations ranging from 5 to 1500 mg l1 due to their poor fixation to fabrics Moreover, reactive azo dyes are not degraded by conventional aerobic sewage treatment plants as they are resistant to biological
oxidative degradation Decolourisation can be achieved using either anaerobi digestion, microbial generation of oxygen radicals,
i.e. laccase activity of white-rot fungi or expensive physico-chemical treatments