Kinetics of plutonium(4) reaction and aminoguanidine and its catalysis by technetium(7) ions
- 1. GNTs RF VNII Neorganicheskikh Materialov im. akad. A.A. Bochvara, Moscow (Russian Federation)
Description
Aminoguanidines acting as salt-free reducing agent of Pu(4) to separate U, Pu and Np in the Purex-process were studied for the first time. Tc(7) ion catalysis of Pu(4) reducing reaction using aminoguanide in nitrate medium was studied as aqueous and organic solutions of spent nuclear fuel usually contained Tc(7) ions when separating U, Pu and Np. -d[Pu(4)]/dt k[Pu(4)][HNC(NH2)N2H4+]/[H+] where k = 0.130±0.007 min-1 under 35.1 deg C and μ = 2 solution ion concentration reaction was determined to describe the rate of non catalyzed reaction. Activation energy was equal to 100 kJ/mole. The rate of catalytic reaction was described by -d[Pu(4)]/dt k2[Tc(7)][HNC(NH2)N2H4+] x [H+]1.5 where k = (5.17±0.86) x 10-2 l2.5/(mole2.5 x min) under 35/1 deg C and μ = 2. The activation energy constituted 37 kJ/mole. The catalysis mechanism was determined. It was clear that even in case when Tc(7) concentration equalled to 1x10-3 mole/l the reaction of Pu(4) reduction using animoguanidine was accelerated by 1.5 time
Abstract (Russian)
Рассмотрены впервые аминогуанидины в качестве бессолевых восстановителей Pu(4) для разделения U, Pu и Np в Пурекс-процессе. Рассмотрен катализ реакции восстановления Pu(4) в азотнокислой среде аминогуанидином ионами Tc(7), поскольку они обычно присутствуют в водных и органических растворах отработавшего ядерного топлива на операции разделения U, Pu, Np . Установлено, что скорсоть некатализируемой реакции описывается уравнением -d[Pu(4)]/dt = k[Pu(4)][HNC(NH2)N2H4+]/[H+], где k = 0,130±0,007 мин-1 при 35,1 град. С и ионной силе раствора μ = 2. Энергия активации равна 100 кДж/моль. Скорость каталитической реакции соответствует уравнению -d[Pu(4)]/dt = k2[Tc(7)][HNC(NH2)N2H4+] x [H+]1,5, где k (5,17±0,86) x 10-2 л2,5/(моль х мин) при 35,1 град. С и μ = 2. Энергия активации составляет 37 кДж/моль. Обсуждается механизм катализа. Видно, что даже при концентрации Tc(7) 1x10-3 моль/л реакция восстановления Pu(4) аминогуанидином ускоряется в 1,5 разаAdditional details
Additional titles
- Original title (Russian)
- Кинетика реакции междфу плутониум(4) и аминогуанидином и катализ ее ионами технеция(7)
Publishing Information
- Journal Title
- Radiokhimiya
- Journal Volume
- 42
- Journal Issue
- 1
- Journal Page Range
- p. 65-68
- ISSN
- 0033-8311
- CODEN
- RADKAU
INIS
- Country of Publication
- Russian Federation
- Country of Input or Organization
- Russian Federation
- INIS RN
- 31036888
- Subject category
- S38: RADIATION CHEMISTRY, RADIOCHEMISTRY AND NUCLEAR CHEMISTRY; S11: NUCLEAR FUEL CYCLE AND FUEL MATERIALS;
- Descriptors DEI
- ACTIVATION ENERGY; AMINES; AQUEOUS SOLUTIONS; CATALYSIS; CHEMICAL REACTION KINETICS; CHEMICAL REACTIONS; CONCENTRATION RATIO; GUANIDINES; NITRIC ACID; PLUTONIUM; PUREX PROCESS; TECHNETIUM COMPOUNDS; TEMPERATURE RANGE 0273-0400 K
- Descriptors DEC
- ACTINIDES; CARBONIC ACID DERIVATIVES; DISPERSIONS; ELEMENTS; ENERGY; HYDROGEN COMPOUNDS; INORGANIC ACIDS; INORGANIC COMPOUNDS; KINETICS; METALS; MIXTURES; NITROGEN COMPOUNDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; OXYGEN COMPOUNDS; REACTION KINETICS; REFRACTORY METAL COMPOUNDS; REPROCESSING; SEPARATION PROCESSES; SOLUTIONS; TEMPERATURE RANGE; TRANSITION ELEMENT COMPOUNDS; TRANSURANIUM ELEMENTS
Optional Information
- Notes
- 10 refs.; 2 tabs.; 3 figs.