The transition from used fuel container corrosion under oxic conditions to corrosion in an anoxic environment
Elham Salehi Alaei, Mengnan Guo, Jian Chen, Mehran Behazin, Erik Bergendal, Christina Lilja, David W. Shoesmith, James J. Noël
Abstract
Abstract The conversion of copper oxide films on copper to copper sulfide has been investigated in sulfide‐containing chloride solutions. Single‐phase Cu 2 O films and duplex films consisting of Cu 2 O and CuO, and possibly Cu(OH) 2 , were prepared electrochemically on copper specimens at various applied potentials and characterized using Raman spectroscopy, scanning electron microscopy, and energy dispersive X‐ray analyses. The surface condition of the specimens subsequently exposed to a solution containing sulfide was monitored by measuring the corrosion potential ( E corr ) for various exposure periods, then cathodic stripping voltammetry was performed. Cuprite (Cu 2 O) was observed to be converted to Cu 2 S by chemical reaction with sulfide, while the conversion mechanism for the mixed deposit could comprise a galvanic process involving Cu II reduction coupled to the formation of Cu 2 S by the reaction of sulfide with copper within pores in the Cu 2 O/CuO surface film and a chemical conversion of Cu 2 O to Cu 2 S. Cupric hydroxide was not converted to Cu 2 S on the time scale (24 h) of these experiments.