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DOE OSTI · 1649424

Density Calculations of Actinide Solutions using the Pitzer Method

Weber, Charles F.·Hite, Jason·Alwin, Jennifer
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Abstract

This report summarizes an exhaustive literature search for density data of actinide solutions in support of the Nuclear Criticality Safety Program (NCSP). This work comprises an extension of work originally begun in 2003 that implemented an advanced density calculation scheme in the SCALE material input processor. This method demonstrated improved criticality calculations for aqueous systems of UO 2 (NO 3 ) 2 and Pu(NO 3 ) 4 in excess acid over a considerable range of concentrations and temperatures. It also provided for UO 2 F 2 in acid at room temperature, although with higher uncertainty. The current study was intended to search all available sources for additional data on uranium and plutonium solutions, including the open literature, reports with limited distribution, and unpublished sources such as laboratory notebooks. Data for some of the systems has been regressed to obtain model parameters for the Pitzer formalism of modeling electrolyte solutions.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAnalytical MethodsElectrolyte SolutionsNuclear Criticality Safety Program (NCSP)

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Weber, Charles F., Hite, Jason, Alwin, Jennifer. 2019-12-01. Density Calculations of Actinide Solutions using the Pitzer Method. https://doi.org/10.2172/1649424

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