Study on the Behavior of Radiolytically Produced Hydrogen in a High-Level Liquid Waste Tank of a Reprocessing Plant: Hydrogen Consumption Reaction Catalyzed by Pd Ions in the Simulated Solution

Density Functional Theory Study on the 193Ir Mössbauer Spectroscopic Parameters of Vaska’s Complexes and Their Oxidative Adducts

“…Since they are much more abundant in high-level radioactive liquid waste (>10 –1 g L –1 ) than in the Earth’s crust (<10 –3 ppm), the recovery of platinum-group metals from high-level radioactive liquid waste is expected to provide a valuable source of platinum-group metals to be used mainly as catalysts. Moreover, Kodama et al indicated that hydrogen (H 2 ) gas generation in high-level radioactive liquid waste by radiolysis reaction of the solvent decreases in the presence of Pd . The Pd ion was predicted to catalyze the conversion of NO 3 – into NO or NO 2 upon reaction with the H 2 molecule .…”

“…Following our work on platinum-group metal complexes, we were interested in predicting the mechanism of the catalytic reaction of the Pd 2+ ion with H 2 in high-level radioactive liquid waste solution, described by Kodama and co-workers, using DFT calculation. The Pd–H 2 complex was also previously shown to catalyze the conversion of CO 2 into HCOO – in aqueous alkali solution .…”

“…Moreover, Kodama et al indicated that hydrogen (H 2 ) gas generation in high-level radioactive liquid waste by radiolysis reaction of the solvent decreases in the presence of Pd. 6 The Pd ion was predicted to catalyze the conversion of NO 3 − into NO or NO 2 upon reaction with the H 2 molecule. 6 However, the mechanism of this catalytic reaction has never been clarified, despite its obvious importance for safety evaluation in light water reactors.…”

“…6 The Pd ion was predicted to catalyze the conversion of NO 3 − into NO or NO 2 upon reaction with the H 2 molecule. 6 However, the mechanism of this catalytic reaction has never been clarified, despite its obvious importance for safety evaluation in light water reactors.…”

Complexation and bonding studies on [Ru(NO)(H2O)5]3+ with nitrate ions by using density functional theory calculation

“…5 The catalytic activity has been indicated to reduce the hydrogengeneration in HLLW solution as well as to generate NO 2 and NO. 6 The efficient separation of PGMs from HLLW has been studied for the efficient disposal of HLLW and reuse as the PGM resource by means of solvent extraction, ionic exchange, and the other techniques. [7][8][9] In order to understand the separation mechanism, the coordination species of PGMs in HLLW solution need to be elucidated.…”