Degradation of pyrazinamide in aqueous solution by electron beam irradiation: kinetics, influence factors and mechanism study

The degradation of pyrazinamide (PZA) by electron beam irradiation (EBI) was studied. It was found that the degradation of PZA was efficient with the removal rate of 99% for 0.2 mM PZA under 5 kGy, and the degradation kinetics followed pseudo-first-order kinetics. The presence of CO 3 2− , HCO 3 − , NO 3 − , and fulvic acid inhibited the degradation of PZA. The addition of H 2 O 2 or K 2 S 2 O 8 effectively enhanced the degradation and mineralization of PZA. The scavenger experiments and quantum chemical calculations showed that · OH was the primary reactive species in the degradation. The identification of intermediates and quantum chemical calculations illustrated the mechanism of degradation.