Principal reactions of airborne mercury,ozone and some other microcomponent in pure water or very dilute sulfuric acid

Numerous bubblings of pure H₂O or very dilute H₂SO₄-solutions with ambient air have been undertaken. All of them have shown the formation of HgIIa and HgIIb in the liquid phase (nomenclature according to Brosset, 1987). With increasing air volume such systems clearly approach a steady state. Earlier it has been shown that Hg° in water is oxidized by O₃ primarily to Hg²⁺, (Brosset, l.c., Iverfeldt and Lindqvist, 1986, Munthe, Thesis 1991). However, the attainment of a steady state indicates that a reaction involving a removal of Hg from the solution must exist as well. It has now been anticipated that a substance ‘X’, present in the ambient air, should be responsible, at least partly, for this removal. Starting from this assumption a model has been developed, which seems to be supported by all experimental tests hitherto performed by us. Further it has been tried to establish the chemical nature of ‘X’. So far, some experiments show that ‘X’ may be (CH₃)₂S. Finally it has been shown that HgIIb observed in precipitation is not identical with the corresponding compound formed by bubbling of ambient air at the ground level through it.