Chemical Speciation of Inorganic Compounds under Hydrothermal Conditions

摘要

By employing XAFS spectroscopy we are seeking a better understanding of the high temperature aqueous chemistry and speciation of those components that are troublesome to the treatment of the Hanford tank wastes: namely Cr, Re (surrogate for Tc), Fe, Ru (surrogate for Pu), and NO3 -/NO2 -. After initial experiments revealed that the high corrosivity of some of these aqueous systems renders the original high-pressure/high-temperature XAFS flow cell unsuitable of these systems, we have quickly implemented a new XAFS flow cell design made from Pt/Ir alloy. Over the last 12 months we have been able to obtain a number of groundbreaking results with this new XAFS cell, which we will briefly highlight.