Biological decolorization of textile dyestuff by Coriolus versicolor in a packed column reactor

Biological decolorization of textile dyestuff Everzol Turquoise Blue G, a phthalocyanin type reactive dyestuff, by white-rot fungi Coriolus versicolor MUCL was studied in a packed column reactor. Decolorization performance of fungi immobilized on different support particles such as metal mesh, sponge, stone, wood ash, polyurethane and wood particles were investigated in shake flasks. Metal mesh particles was found to be superior to the other immobilization matrices resulting in 97% decolorization efficiency. The packed column reactor containing fungi immobilized on metal mesh particles was operated in repeated-batch mode. The reactor was loaded 7 times with fresh colored media in every 24 hours. The reactor was gently aerated by a diffuser from the bottom of the column. Environmental conditions were adjusted to T = 28°C and pH = 4.5-5.0. TOC, glucose and dyestuff concentrations were determined throughout the experiments. During the course of repeated batch operation, decolorization efficiency decreased from 99% to 50% in seven days. Operation of the reactor with 50-100-200 mg l^-1 feed dyestuff concentrations resulted in 50% decolorization and 80% TOC removal efficiency in seven days.