Kinetics and mechanisms of reactions between H₂O₂and copper and copper oxides

Abstract

One of the main challenges for the nuclear power industry today is the disposal of spent nuclear fuel. One of the most developed methods for its long term storage is the Swedish KBS-3 concept where the spent fuel is sealed inside copper canisters and placed 500 meters down in the bedrock. Gamma radiation will penetrate the canisters and be absorbed by groundwater thereby creating oxidative radiolysis products such as hydrogen peroxide (H2O2) and hydroxyl radicals (HO˙). Both H2O2 and HO˙ are able to initiate corrosion of the copper canisters. In this work the kinetics and mechanism of reactions between the stable radiolysis product, H2O2, and copper and copper oxides were studied. Also the dissolution of copper into solution after reaction with H2O2 was monitored by ICP-OES. The experiments show that both H2O2 and HO˙ are present in the systems with copper and copper oxides. Nevertheless, these species do not appear to influence the dissolution of copper to the same extent as observed in recent studies in irradiated systems. This strongly suggests that aqueous radiolysis can only account for a very minor part of the observed radiation induced corrosion of copper.

Confirming the Formation of Hydroxyl Radicals in the Catalytic Decomposition of H2O2 on Metal Oxides Using Coumarin as a Probe

“…This method was first used to detect hydroxyl radicals produced upon catalytic decomposition of H 2 O 2 on ZrO 2 . Following the first study on ZrO 2 , numerous experimental studies on other oxides have been performed . In many studies, methanol has been used as a scavenger for the hydroxyl radical.…”

“…[5] Following the first study on ZrO 2 , numerous experimental studies on other oxides have been performed. [6,9,10] In many studies, methanol has been used as a scavenger for the hydroxyl radical. Also, this reaction produces formaldehyde.…”

“…Both tris and methanol have also been used to quantify hydroxyl radicals produced by heterogeneous photocatalysis. [10] Although very useful in assessing hydroxyl radical formation in heterogeneous systems, it should be kept in mind that the reaction with either tris or methanol yielding formaldehyde is not necessarily unique for hydroxyl radicals. In principle, any radical species capable of abstracting a hydrogen atom from tris or methanol will produce formaldehyde.…”

Kinetic and Mechanistic Study of Rhodamine B Degradation by H2O2 and Cu/Al2O3/g-C3N4 Composite

“…Thus, in this work, the catalyst dose is represented by surface area concentration (SA/V), which is the product of mass concentration (g/L) and specific surface area (m 2 /g) and has a unit of m −1 . The concept of surface area concentration was first proposed by Matheson and Tratnyek as a general independent variable to correlate with the contaminants removal rate constants, as it incorporates most of the effects of grain size and shape [55], and now it is widely used in many heterogeneous systems for kinetic study [35,[56][57][58][59]. One example for the unit conversion is exhibited in Equation 5, with a mass concentration of 1 g/L and the specific surface area of 146.6 m 2 /g for the Cu/Al 2 O 3 /CN composite.…”

Gamma radiation induces hydrogen absorption by copper in water

“…Additionally, γ-radiation is known to cause low temperature annealing of metals31. The fact that γ-radiation is capable of inducing structural changes in the bulk material32 and interface with water21—including corrosion333435—lead us to develop this study, which is aimed at understanding whether γ-radiation is capable of triggering the uptake of hydrogen by high-purity metallic copper in aqueous medium. As shown above, one of the radiolysis products of water is hydrogen36.…”