title: Decay Mechanism of NO3(•) Radical in Highly Concentrated Nitrate and Nitric Acidic Solutions in the Absence and Presence of Hydrazine.
abstract: The decay mechanism of NO3(•) has been determined through a combination of experiment and calculation for 7 mol dm(-3) solutions of deaerated aqueous LiNO3 and HNO3, in the absence and presence of hydrazine (N2H4, N2H5(+), and N2H6(2+)). In the absence of hydrazine, the predominant NO3(•) decay pathways are strongly dependent upon the pH of the solution. For neat, neutral pH LiNO3 solutions (7 mol dm(-3)), NO3(•) produced by the pulse is fully consumed within 160 μs by OH(•) (37%), H2O (29%), NO2(-) (17%), and NO2 (17%). For acidic HNO3 solutions (7 mol dm(-3)), radiolytically produced NO3(•) is predominantly consumed within 1 ms by HNO2 (15%) and NO2 (80%). Intervening formulations exhibit the mechanistic transition from neat LiNO3 to neat HNO3. In highly acidic nitric acid solution, hydrazine exists mainly as N2H5(+) and N2H6(2+), both of which rapidly consume NO3(•) in addition to other decay mechanisms, with rate constants of 2.9 (±0.9) × 10(7) and 1.3 (±0.3) × 10(6) dm(3) mol(-1) s(-1), respectively.
authors.affiliation: French Alternative Energies and Atomic Energy Commission, CEA , Nuclear Energy Division, Radiochemistry & Processes Department, DRCP, BP 17171, F-30207 Bagnols sur Cèze, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Garaix
authors.affiliation: Laboratoire de Chimie Physique, CNRS/Université Paris-Sud , Bâtiment 349, 91405 Orsay, France.|The University of Manchester Dalton Cumbrian Facility , Westlakes Science and Technology Park, Moor Row, Cumbria, CA24 3HA, United Kingdom.|School of Chemistry, The University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Horne
authors.affiliation: French Alternative Energies and Atomic Energy Commission, CEA , Nuclear Energy Division, Radiochemistry & Processes Department, DRCP, BP 17171, F-30207 Bagnols sur Cèze, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Venault
authors.affiliation: French Alternative Energies and Atomic Energy Commission, CEA , Nuclear Energy Division, Radiochemistry & Processes Department, DRCP, BP 17171, F-30207 Bagnols sur Cèze, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Moisy
authors.affiliation: The University of Manchester Dalton Cumbrian Facility , Westlakes Science and Technology Park, Moor Row, Cumbria, CA24 3HA, United Kingdom.|School of Chemistry, The University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
authors.forename: Simon M
authors.initials: SM
authors.lastname: Pimblott
authors.affiliation: Laboratoire de Chimie Physique, CNRS/Université Paris-Sud , Bâtiment 349, 91405 Orsay, France.
authors.forename: Jean Louis
authors.initials: JL
authors.lastname: Marignier
authors.affiliation: Laboratoire de Chimie Physique, CNRS/Université Paris-Sud , Bâtiment 349, 91405 Orsay, France.
authors.forename: Mehran
authors.initials: M
authors.lastname: Mostafavi