Home > Research > Publications & Outputs > The development of a method for the simultaneou...
View graph of relations

The development of a method for the simultaneous measurement of cerium (iv) and chromium (vi) species in nitric acid media

Research output: Contribution in Book/Report/Proceedings - With ISBN/ISSNConference contribution/Paperpeer-review

Published
Close
Publication date12/12/2010
Host publicationASME 12th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM09): Volume 1: Low/Intermediate-Level Waste Management; Spent Fuel, Fissile, Transuranic, High-Level Waste Management
Place of PublicationNEW YORK
PublisherAMER SOC MECHANICAL ENGINEERS
Pages163-169
Number of pages7
ISBN (print)978-0-7918-4407-6
<mark>Original language</mark>English

Abstract

The corrosion of stainless steel in nitric acid media is a major concern for the nuclear industry. Several reprocessing schemes such as PUREX (Plutonium Uranium Reduction Extraction) and UREX (Uranium Reduction Extraction) utilise nitric acid media, and an understanding of the behaviour of key chemical species in these process streams is vital if their effect on associated corrosion reactions and their rates is to be accurately assessed and quantified. This will allow for more accurate prediction of the working lifetime of any stainless steel surface in contact with the process stream in question.

Two such key species that are found in nuclear process streams are cerium as Ce (IV) and chromium as Cr(VI), both of which may act as corrosion accelerants. The redox chemistry of cerium and chromium in highly active liquor (HAL) will depend on nitrous acid concentration, temperature, acidity, total nitrate and possibly the influence of other dissolved species and hence an analytical technique for the on-line measurement of these quantities would be useful for lifetime prediction and corrosion prevention.

As a result of this, a strategy for the simultaneous measurement of both Ce(IV) and Cr(VI) species in the presence of other ions typically found in process streams (such as Iron, Magnesium Neodymium and Aluminium) has been developed. The work presented will discuss the design and implementation of the electrochemical techniques that we have used in the development of this strategy and in the measurement of the species in question.