Comparative study on the dissolution behavior of Fe_3O_4, γ-Fe_2O_3 and NiFe_2O_4 in DCD formulation-a mechanistic approach

摘要

In water-cooled nuclear reactors, various corrosion products are formed by the interaction of structural alloy surfaces with high temperature water. The major corrosion products deposited are Fe_3O_4 (Magnetite), Fe (Ⅲ) oxides and Nickel ferrite. The dissolution of these oxides depends on various factors like structure of the oxide, the formulation used for dissolution, temperature, reductant and the pH of the formulation. The leaching of the metal ions is effectively controlled by reductive reaction, which is a heterogeneous electron transfer reaction between the oxide surface and the reductant. This study deals with the comparative account of the dissolution behavior of Fs_3O_4 γ-Fe_2O_3 and nickel ferrite in 2,6-pyridinedicarboxylic acid (PDCA), nitrilotriacetic acid (NTA), ethlenediaminetetraacetic acid (EDTA) and thioglycolic acid along with reductants like AA and Fe~(2+)-L complex.