INITIAL-STAGES OF COPPER CORROSION IN HUMID AIR CONTAINING SO2 AND NO2

We report on the reaction of SO2 and NO2 in sub-ppm concentrations in humid air with a copper surface. The deposition of SO2 was studied in a time-resolved manner and the formation of HNO2 was measured. Corrosion products were analyzed using XRD, FTIR, FTIRAS, and ion chromatography. S(IV)-O species on the copper surface was analyzed quantitatively using a sensitivity of 10-(11) mol. Corrosion rates and corrosion products are reported. The corrosion of copper in humid SO2-polluted air is accelerated strongly by the presence of NO2.