Simultaneous voltammetric determination of uranium and plutonium in FBTR fuel on PEDOT : PSS modified glassy carbon electrode

Chemical quality control of nuclear fuels is essential for smooth operation of nuclear reactors. Thus very accurate and precise measurement of U and Pu content in nuclear fuel is must in order to get the desired performance of the fuel inside the reactor. A large number of destructive and non-destructive analytical techniques are available for (U, Pu) determination, but redox titrimetric methods offers several advantages over other techniques if cost, time, precision, accuracy, space, analysts' effort etc are all together taken into account. Although, biamperometry is routinely employed to determine U and Pu contents in nuclear fuel samples in our laboratories, it too suffers from a major disadvantage. Recovery of precious Pu and U from analytical waste is a cumbersome process, because it requires the separation of various metallic impurities (Fe, Cr, Ti, Ag, K, etc.) present in the redox titrants added during the analysis. Also, biamperometry requires separate solutions for the determination of U and Pu in the same sample. Controlled-potential coulometry is an alternative electrochemical method without any need of chemical titrants, but it is a time-consuming and very often suffers from the passivation of the working electrode which further increases the analysis time. Here, we report a cyclic voltammetry techniques for simultaneous U and Pu determination in FBTR fuels which is very accurate, precise, fast, require very small volume of solution and produce clean analytical waste. This method shows accuracy and precision comparable to those of the biamperometry method. High robustness, fast analysis, simultaneous determination, reduced radiation exposure to the analyst, and ease of recovery of U and Pu from analytical waste makes it a suitable candidate to substitute the presently applied biamperometry method. (author)