Аннотация:This paper considers the data on monitoring the ionic composition of aerosol particles and smallgas components in the surface atmosphere of Antwerp and Beijing in winter. According to the results of theircomparison, it is shown that the rapid accumulation of in haze particles over Beijing is triggered by aliquid-phase catalytic reaction of sulfate formation involving Mn/Fe ions, which proceeds in the fast degeneratebranched mode. The cycle of these transformations is accompanied by the associated production ofnitrate radicals in the particles. Their release into the gas phase leads to an increase in the concentration ofN2O5 molecules and a rapid accumulation of nitrates. The coupling of the catalytic (petrochemical) conversionof sulfur dioxide into sulfates and the nitrate production process over Beijing thus plays a crucial role inthe formation of the mineral composition of haze particles in the atmosphere.