Neptunium electrolytic reduction

Naptbol, l-(2-carboxyphenyla2o)-chromium complex geometrical isomerism, 68 Neptunium breeder reactor fuels Purex process, 955 reprocessing, 954 electrolytic reduction Purex process, 949 environmental chemistry, 961 extraction Purex process, 951 Purex process, 946,950 recovery... 

The second part of Table 10.22 gives equations for the concentration ratio of tetravalent to pentavalent neptunium calculated for the three reductants listed there. In the older Purex plants the ferrous sulfamate used to reduce plutonium to inextractable Pu reduced neptunium partly to inextractable Np(V) and partly to extractable Np(IV). The reductants now preferred, tetravalent uranium (possibly made electrolytically) or hydroxylamine, are sufficiently strong, in sufficient time, to make neptunium almost completely tetravalent, but the reactions are much slower than reduction of tetravalent plutonium, because of slow deoxidation of the NpOj radical. Kinetics of these reductions are also discussed in Sec. 7.5. 

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