Articles | Volume 14, issue 6
https://doi.org/10.1007/s00585-996-0659-5
https://doi.org/10.1007/s00585-996-0659-5
30 Jun 1996
30 Jun 1996

Heterogeneous loss of OH on NaCl and NH4NO3 at tropospheric temperatures

A. V. Ivanov, Y. M. Gershenzon, F. Gratpanche, P. Devolder, and J.-P. Sawerysyn

Abstract. The uptake coefficients (Γ) for OH radicals on some dry salts of tropospheric interest (NaCl and NH4NO3) have been investigated as a function of temperature using the flow tube technique combined with an EPR spectrometer as a detection method. The temperature dependence of Γ-values measured over the temperature range 245–340 K can be expressed in Arrhenius form: ΓOHNaCl=(1.2±0.7)×10–5exp[(1750±200)/T] and ΓOHNH4NO3=(1.4±0.5)×10–4exp[(1000±100)/T]. These Arrhenius expressions lead to very similar Γ-values (~4×10–3) for both salts studied at 300 K. It is shown that the heterogeneous OH sinks on solids aerosol play a very minor role in tropospheric chemistry in comparison with the homogeneous sinks.