[Characteristics and Mechanisms of Bacteriophage MS2 Inactivation in Water by UV Activated Sodium Persulfate].

Viruses in the aquatic environment have strong resistance to common disinfection techniques. To contribute to the development of efficient virus inactivation technologies, the characteristics and mechanisms of virus inactivation in a UV activated sodium persulfate(UV/PS) system were studied. The inactivation rate and kinetic characteristics of bacteriophage MS2 in water samples by the UV/PS were studied. The effects of PS dosage, pH, and the initial concentration of bacteriophages on the inactivation effect were also investigated. Furthermore, the morphologies of phages before and after UV/PS treatment were observed by transmission scanning electron microscope, and the free radicals in the reaction system were identified by electron paramagnetic resonance spectroscopy. By means of a free radical quenching experiment, the contribution rate of various factors in the UV/PS system to phage inactivation was also analyzed and calculated. The results showed that when the UV irradiation intensity was 160 μW·cm ^-2 , the phage MS2 of 4.39 lg could be removed after UV/PS treatment for 4 min, which was 1.44 lg higher than that of the same UV dose alone. The inactivation of phage MS2 by the UV/PS system was in accordance with the first-order kinetic model. Increasing the initial concentration of PS in the system significantly improved the inactivation rate of phages, while pH and the initial concentration of phages had little effect on the inactivation rate. UV/PS treatment damages the capsid of phages and promotes the aggregation of phage particles. The presence of SO ₄ ^- · and·OH in the UV/PS system was an important factor for the inactivation of MS2 phages. Finally, ·OH contributed more to MS2 phage inactivation than SO ₄ ^- ·.