Original paper(Vol.48 No.11 pp.1239)

Photocatalystic effect of rust on acid rain corrosion of carbon steel

Kumada Makoto; Shinoda Kazuya; Kobuchi Shigetoshi; Niwa Kiyoko; Yamada Takahiro

Abstract:The effect of ultra-violet (UV) light irradiation on corrosion behavior of carbon steel in acid rain was investigated by immersion tests and electrochemical measurement. From the result it was found that (1) corrosion loss of the steel in artificial acid rain increased with decrease of solution pH, (2) corrosion loss and anodic current density of the steel under UV irradiation was larger than those without UV irradiation, and (3) the effect of UV irradiation on corrosion of the steel increased with immersion time. It is considered that the rust on the carbon steel acts as a photocatalyst and to enhance the corrosion in acid rain. From a semiconductive property of the rust, we proposed an enhancement mechanism of the corrosion by UV light irradiation.

Key Words:carbon steel, acid rain corrosion, UV irradiation, photocatalystic effect