Electron beam irradiation of citric acid aqueous solutions containing persulfate

The electron beam irradiation of aqueous solutions of citric acid was studied. The results showed the effectiveness of the degradation of the carboxylic acid by the radiation process. The impact of pH was examined. It was demonstrated that the increase of pH induces a drop of the degradation due to the scavenging of radicals by the inorganic carbon. Moreover the interest of persulfate (S2O82-) addition that induces the formation of sulfate radicals (SO4-) by the reaction of persulfate with the hydrated electrons was studied. The addition of persulfate leads to a great enhancement of the degradation of the carboxylic acid and also a large increase of the mineralization of the solution. Effectively, it was shown that the particular reactivity of the sulfate radical causes an enhancement of the mineralization yield.

► Data about the role of sulfate radicals in the degradation of citric acid by e-beam.
► The effect of the sulfate radical concerning the mineralization yield.
► The influence of pH in the radiation system.
► Results are completed by a kinetic approach.