DXRD studies of sodium nickel ferrocyanide reactions with equimolar nitrate/nitrite salts

Journal Article · Sun May 01 00:00:00 EDT 1994 · Environmental Science and Technology; (United States)

DOI:https://doi.org/10.1021/es00054a020· OSTI ID:7110766

Dodds, J N; Thomson, W J ^[1]

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1. Washington State Univ., Pullman, WA (United States)

Dynamic X-ray diffraction (DXRD) has been used to identify and quantify the solid-state reactions that take place between sodium nickel ferrocyanide, Na[sub 2]NiFe(CN)[sub 6], and equimolar concentrations of sodium nitrate/nitrite, reactions of interest to the continued environmental safety of certain waste storage tanks at the Hanford site in eastern Washington. The results are supportive of previous work that indicated that endothermic dehydration and melting of the nitrates take place prior to the occurrence of exothermic reactions, which begin about 300[degree]C. The DXRD results show that a major reaction set at these temperatures is the occurrence of a series reaction which produces sodium cyanate, NaCNO, as an intermediate in a mildly exothermic first step. In the presence of gaseous oxygen, NaCNO subsequently reacts exothermally and at a faster rate to form metal oxides. Measurements of the rate of this reaction are used to estimate the heat release, and comparisons of this with heat-transfer rates from a hypothetical [open quotes]hot spot[close quotes] show that, even in a worse case scenario, the heat-transfer rates are approximately eight times higher than the rate of energy release from the exothermic reactions. 20 refs., 7 figs., 3 tabs.

• OSTI ID: 7110766
• Journal Information: Environmental Science and Technology; (United States), Vol. 28:5; ISSN 0013-936X
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CESIUM 137
SCAVENGING
FERROCYANIDES
CHEMICAL REACTIONS
NITRATES
DEHYDRATION
MELTING
NITRITES
URANIUM ORES
PROCESSING
CHEMICAL REACTION KINETICS
COMPILED DATA
HANFORD RESERVATION
HEAT TRANSFER
NICKEL COMPOUNDS
RADIOACTIVE WASTE STORAGE
SODIUM COMPOUNDS
X-RAY DIFFRACTION
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CESIUM ISOTOPES
COHERENT SCATTERING
COMPLEXES
DATA
DIFFRACTION
ENERGY TRANSFER
INFORMATION
INTERMEDIATE MASS NUCLEI
IRON COMPLEXES
ISOTOPES
KINETICS
MANAGEMENT
NATIONAL ORGANIZATIONS
NITROGEN COMPOUNDS
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
ORES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
RADIOACTIVE WASTE MANAGEMENT
RADIOISOTOPES
REACTION KINETICS
SCATTERING
STORAGE
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENT COMPOUNDS
US DOE
US ERDA
US ORGANIZATIONS
WASTE MANAGEMENT
WASTE STORAGE
YEARS LIVING RADIOISOTOPES
052001* - Nuclear Fuels- Waste Processing
400201 - Chemical & Physicochemical Properties