Effect of sulphide on the corrosion behaviour of AISI 316L stainless steel and its constituent elements in simulated Kraft digester conditions

• DOI: 10.1016/j.corsci.2009.12.034
• Publication Date: 2010-01-12T10:00:28Z
• Authors: Iva Betova; Martin Bojinov; Outi Hyökyvirta; Timo Saario
• Keywords: Reactor conditions; Cyclic voltammetry; EIS; 0202 electrical engineering, electronic engineering, information engineering; Passive films; 02 engineering and technology; 0210 nano-technology; Stainless steel

The electrochemical behaviour of AISI 316L steel and its constituent metals in simulated Kraft digester white liquor at 170 °C has been studied by registering slow scan rate voltammograms and impedance spectra at the corrosion potential. Interpretation of the results in terms of two approaches – the Mixed-Conduction Model for passive films and a two-step dissolution reaction – allowed for the estimation of corrosion currents and polarisation resistances as depending on the material and electrolyte medium. Tentative conclusions on the effect of sulphur-containing species in the white liquor on the corrosion mechanism of the studied materials are drawn.