Biodegradation of bezafibrate by the activated sludge under aerobic condition: Effect of initial concentration, temperature and pH

Lab-scale experiments were conducted to investigate the effect of initial concentration, temperature and pH on the removal of bezafibrate (BF) by activated sludge under aerobic condition. The results showed that adsorption of BF onto activated sludge was negligible, and biodegradation was the main removal mechanism of BF. The removal of BF in the aqueous phase by the activated sludge can be described by a pseudo-first-order reaction. The reaction rate constants had a negative relationship with the initial concentration of BF, and dramatically reduced from 0.050 to 0.007 h−1, when the temperature dropped from 20 °C to 10 °C. Variation of pH between 5.0 and 9.0 did not have significant influence on the removal of BF, indicating a high adaptation of microorganism in the activated sludge responsible for BF degradation to a wide pH range. The findings of this study are helpful to improve the removal of pharmaceuticals during the wastewater treatment plants by selecting the appropriate process variables, and eventually eliminate their release to the environment.