Medium-temperature pulsed radiolysis of azeotropic sulfuric acid

The absorption spectra of irradiated azeotropic sulfuric acid were studied in the temperature range of 298-508 K by microsecond-pulsed radiolysis. The absorption maxima of deaerated acid at room temperature at ∼275 and 460 nm were assigned to HSO3 sm-bullet and HSO4 sm-bullet radicals, respectively. In the absorption spectra of an oxygen-saturated acid at room temperature and a deaerated acid at elevated temperatures, an additional absorption band of the HSO5 sm-bullet radical appears in the UV region. The results were used to design a radiolysis mechanism for concentrated sulfuric acid, which qualitatively fits the known experimental facts