Application of the Sono-Fenton and Ozonation Processes in the Degradation of Tetracycline

Abstract

Tetracycline antibiotics are among the largest groups
of pharmaceutical compounds extensively used in human and
veterinary medicine to treat and prevent bacterial infections. In
this study, the sono-Fenton process and ozonation were used to
degrade tetracycline, and the effects of various operational
parameters on tetracycline degradation and its change of toxicity
were investigated. The experimental results indicate that the
effect of the initial pH level of tetracycline degradation was
insignificant from pH 3 to pH 6, but it became increasingly
important as the pH became greater than 7. Increasing the
ultrasonic power slightly increased the degradation efficiency of
tetracycline, suggesting that hydroxyl radicals greatly influence
the oxidation of tetracycline. Additionally, the effects of air or
oxygen aeration with different flows and reaction temperatures
were insignificant. The addition of anions to the reaction solution
inhibited the degradation and mineralization of tetracycline from
90% to 31.5% and from 30% to 7.7%, respectively.
Furthermore, ozonation elicited superior efficiency in
tetracycline degradation, where the optimal reaction conditions
were found at pH 3, 0.2 L O3/min and 25oC with almost 100%
tetracycline degradation and 34% mineralization. The toxicity of
tetracycline was significantly decreased because of
mineralization, where the cell viability increased to 89% and
70% from less than 50% of the original tetracycline solution.