Pentachlorophenol degradation by activated sludge with phenol and glucose as growth substrates

Important factors affecting the effectiveness of microbiological degradation of chlorophenols include the presence of additional growth substrates, which ensure the accessibility of electron acceptors and electron donors, or the applied strains of microorganisms and their adaptation to pollution. Therefore an improvement of PCP degradation by the adaptation of activated sludge to PCP with phenol and glucose as cometabolites was examined. The activated sludge was adapted to 12 mg∙L^-1 of PCP and to 200 mg∙L^-1 of phenol, and then, the effect of the adaptation of activated sludge and the presence of additional sources of carbon and energy on the biodegradation of PCP and sorption properties were tested. The obtained results confirmed that the presence of additional sources of carbon and energy in the growth medium would improve the efficiency of PCP degradation. Among all analyzed types of research setups, the highest PCP degradation was noted in setups with phenol, regardless of the method of activated sludge adaptation or lack of adaptation. The biodegradation of PCP in the presence of glucose was less efficient than in the presence of phenol. The highest, 60% decrease in PCP concentration was obtained for activated sludge adapted to PCP in the presence of phenol.