On the Mechanism of Nitrate Formation in Atmospheric Haze Particles

Abstract

This paper considers the data on monitoring the ionic composition of aerosol particles and small gas components in the surface atmosphere of Antwerp and Beijing in winter. According to the results of their comparison, it is shown that the rapid accumulation of \({\text{NO}}_{3}^{ - }\) in haze particles over Beijing is triggered by a liquid-phase catalytic reaction of sulfate formation involving Mn/Fe ions, which proceeds in the fast degenerate branched mode. The cycle of these transformations is accompanied by the associated production of nitrate radicals in the particles. Their release into the gas phase leads to an increase in the concentration of N₂O₅ molecules and a rapid accumulation of nitrates. The coupling of the catalytic (petrochemical) conversion of sulfur dioxide into sulfates and the nitrate production process over Beijing thus plays a crucial role in the formation of the mineral composition of haze particles in the atmosphere.