Kinetics of the Gas-Phase Reaction HOSO2 + O2 -> HO2 + SO3

Article abstract of DOI:10.1021/j100287a045

A flowing afterglow technique was adapted for use as a chemical ionization detector for kinetic measurements.Reactants and products from a radical flow tube reactor are injected into the flowing afterglow for detection via subsequent ion-molecule reactions.This system has been used to study the reaction HOSO2 + O2 -> HO2 + SO3, which is the second step in the homogeneous gas-phase oxidation of SO2 to H2SO4.Both the HOSO2 reactant and the SO3 product were detected by using Cl^- as the chemical ionization reagent.The rate coefficient, which was determined by monitoring the loss of the HOSO2 reactant, is (4.37 +/- 0.66) x 1E-13 cm³ molecule^-1 s^-1 at 298 K.This result supports earlier studies which claimed that odd hydrogen radicals (HO_x) are catalysts in the gas-phase oxidation of SO2.