Chinese Journal of Chemical Engineering, Vol.13, No.5, 608-614, 2005
NO3- and HSO3- induced corrosion of simulated archaeological iron in humid-acid atmosphere
NO3- and HSO3- induced corrosion of simulated archaeological iron in humid-acid atmosphere was studied by using periodic wet-dry tests. Surface tension tests, electrochemical impedance measurement, stereoscopic microscopy and energy dispersive atomic X-ray analysis (EDAX) were used to investigate the corrosion processes and products. The results of mass loss measurement showed that the corrosion kinetics can be approximately described by Delta W = At-B. With the addition of NO3-, the value of B increases. NO3- acts as an inhibitor in the HSO3-bearing pollutant during the corrosion process. Both the electrochemical impedance measurement and surface tension test confirmed the result of mass loss measurement. In addition, we found that the attack of anions to the metal at the initial corrosion stage was in good agreement with their surface activity.