Pulse radiolysis study of concentrated sulfuric acid solutions. Formation mechanism, yield and reactivity of sulfate radicals

Treatment of perfluoroalkyl acids by heat-activated persulfate under conditions representative of in situ chemical oxidation

“…The pK a of SO 4 •− has not been reported, 39 but it is expected to be less than 2. 44 It has been hypothesized that the neutral H + SO 4 •− ion pair could have a higher rate constant with anions than the SO 4 •− anion alone. 45 The uncertainty of the pK a values for PFOA and SO 4 •− make it difficult to differentiate between these two possible explanations.…”

Charge transfer reactions from tryptophan and tyrosine to sulfur-centered dimer radical cation in aqueous -sulfuric acid medium: a pulse radiolysis study

“…[15][16][17][18][19] This assumption leads us to radiation chemical yield of SO 4 •¯e quals to 0.42 μM/J at 2 μs, which is less than the collective yield of eā q , H [17,19] In the present study, the calculated yield of SO (Fig. 2).…”

“…1). [15][16][17][18][19] A broad transient absorption band centered at~450 nm for sulfate radical anion (SO 4 •¯) has been reported in the radiolysis of concentrated H 2 SO 4 (1-18 M) at 15 ps. [16] Earlier, radiolysis of concentrated H 2 SO 4 has been studied in detail suggesting formation of SO 4 •¯( 450 nm) and some other transients (HSO 3 and HSO 5 ) at higher time point (microseconds).…”

In Situ Thermal Remediation of DNAPL Source Zones

“…Although some studies of reactions with activated persulfate have been done with pH and ionic strength control (e.g., Liang et al, 2003), the risk of side reactions is great because radicals react readily with many common inorganic anions. Furthermore, the risk of significant pH or ionic strength effects on the results reported here is small because the chlorinated ethenes are uncharged, and persulfate and most of the significant radicals are un-protonated even in highly acidic solutions (Jiang et al, 1992).…”