The impact of HS radicals on the measured rate constant of H2S with OH radicals

The rate constant for the reaction of OH radicals and hydrogen sulfide (H2S) was studied in different bath gases (including N2, air, O2 and He) by using relative technique at 298 K. The small difference of the measured rate constants between N2 and those with the presence of O2 suggested possible influence of HS self reaction. Further experiments with NOx presence for scavenging HS demonstrated this assumption. The rate constant of (5.48±0.12) ×10-12 cm3 molecule-1 s-1 obtained with 4.09 ×10-4 mol m3 NO presence may be accurate for estimating the atmospheric lifetime of H2S. The results provided circumstantial evidence that the rapid reaction of HS with N2O is suspected.