Pourbaix diagrams at elevated temperatures: a study of Zn and Sn

Metals in industrial settings such as power plants are often subjected to high temperature and pressure aqueous environments, where failure to control corrosion compromises worker and environment safety. For instance, zircaloy (1.2-1.7 wt.% Sn) fuel rods are exposed to aqueous 250-310 oC coolant in CANDU reactors. The Pourbaix (EH-pH) diagram is a plot of electrochemical potential versus pH, which shows the domains of various metal species and by inference, corrosion susceptibility. Elevated temperature data for tin +II and tin +IV species were obtained using solid-aqueous phase equilibria with the respective oxides, in a batch vessel with in-situ pH measurement. Solubilities, determined via spectroscopic techniques, were used to calculate equilibrium constants and the Gibbs energies of Sn complexes for E-pH diagram construction. The SnOH3+ and Sn(OH) species were incorporated, for the first time, into the 298.15 K and 358.15 K diagrams, with novel G ͦ values determined at 358.15 K.

Name thesis:degree_name

Master of Science (MSc)

Discipline thesis:degree_discipline

Materials Science

Grantor

University of Ontario Institute of Technology

Year dc:date.issued

2012

Author dc:creator

• Palazhchenko, Olga

Advisor dc:contributor.advisor

• Kaye, Matthew H.

• Pourbaix diagrams
• Corrosion
• Elevated temperature
• Solubility

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10155/276

OAI identifier oai:identifier

oai:ontariotechu.scholaris.ca:10155/276