Investigation of zinc as a scale and corrosion inhibitor of carbon steel in artificial seawater

In this paper, the inhibition mechanism of Zn2+ in trace concentration on both the CaCO3 precipitation and corrosion of carbon steel in artificial seawater was investigated using various electrochemical and surface analysis methods. The results showed that zinc ions affect both the nucleation and growth stages of CaCO3 crystallization and the best scale inhibition was achieved at 4 ppm concentration. The corrosion inhibition mechanism of Zn2+ was developed by blocking the cathodic sites on the carbon steel surface. Moreover, addition of 6 ppm zinc ions both before and after the scale deposition significantly diminishes carbon steel corrosion.