Ferrocyanide Safety Project Dynamic X-Ray Diffraction studies of sodium nickel ferrocyanide reactions with equimolar nitrate/nitrite salts

Technical Report · Fri Jul 01 00:00:00 EDT 1994

DOI:https://doi.org/10.2172/10176247· OSTI ID:10176247

Dodds, J N ^[1]

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1. Washington State Univ., Pullman, WA (United States). Dept. of Chemical Engineering

Dynamic X-ray Diffraction (DXRD) has been to 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 several large underground waste storage tanks at the Hanford site in eastern Washington. The results are supportive of previous work, which indicated that endothermic dehydration and melting of the nitrates take place before the occurrence of exothermic reactions that being about 300{degrees}C. The DXRD results show that a major reaction set at these temperatures is the occurrence of a series reaction that 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. Comparisons of this estimated heat release rate with heat transfer rates from a hypothetical ``hot spot`` show that, even in a worst-case scenario, the heat transfer rates are approximately eight times higher than the rate of energy release from the exothermic reactions.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 10176247
• Report Number(s): PNL-10050; ON: DE94017396; TRN: 94:020094
• Resource Relation: Other Information: PBD: Jul 1994
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HANFORD RESERVATION
WASTE MANAGEMENT
NITRITES
CHEMICAL REACTIONS
FERROCYANIDES
SODIUM NITRATES
X-RAY DIFFRACTION
NICKEL COMPOUNDS
TANKS
UNDERGROUND STORAGE
BENCH-SCALE EXPERIMENTS
SAFETY
SODIUM COMPOUNDS
052002
054000
400201
WASTE DISPOSAL AND STORAGE
HEALTH AND SAFETY
CHEMICAL AND PHYSICOCHEMICAL PROPERTIES