U.S. Department of Energy

Pacific Northwest National Laboratory

Dallas Reilly

NPSI Project Manager, Scientist
Dallas Reilly
(509) 375-7382

In 2012-2013, Dr. Reilly participated in a project that analyzed the natural aging and oxidation of uranium oxides that, under certain conditions, produces the hydrated uranium trioxide metaschoepite (UO32H2O). In 2013-2014, he extended this initial work and performed in-depth analysis of the growth and development of uranium trioxide phases under artificial annealing conditions in air, as a function of annealing time and temperature and starting material. The uranium-oxygen system has been studied in detail for extreme conditions in the literature, but few certainties in the formation of uranium trioxide phases under industrial processing conditions exist. Utilizing different uranium precursors commonly used in industrial processes, such as ammonium uranyl carbonate ((NH4)4UO2(CO3)3, AUC) and uranyl peroxide (UO4), various uranium trioxide compounds were produced by thermal oxidation in air at varying conditions of time and temperature, and the resulting compounds were analyzed by powder XRD, SEM, and micro-Raman spectroscopy. Some of the significant discoveries made in this FY include some of the first Raman spectra on a number of UO3 phases, a phase diagram including the ranges of conditions that produce phases such as β-UO3 and γ-UO3, and answers to some basic questions not outlined in the literature (i.e. why does washed vs unwashed uranyl peroxide matter for producing α-UO3?). 

Dr. Reilly was instrumental in the preparation of materials for the International Technical Working Group Collaborative Materials Exercise in 2013. His previous experience made him a good candidate for this project, and included work at PNNL with controlled thermal oxidation of the materials and analysis of the prepared materials by SEM, XRD, and thermogravimetric analysis. After this preparation, Dallas worked for two weeks in Australia preparing the final materials and helping arrange for shipping back to the United States.

Education and Credentials

  • Bachelor's Degree, Chemistry, Carthage College (Kenosha, WI).
  • Doctorate, Radiochemistry, University of Nevada.
  • Postdoctoral Fellow, Postdoctoral Research Fellow in the Radiochemical Analysis Group, Pacific Northwest National Laboratory.

Affiliations and Professional Service

  • National Technical Nuclear Forensics Center Postdoctoral Fellow, Pacific Northwest National Laboratory (2013-Present)
  • Seaborg Graduate Fellow, Los Alamos National Laboratory (2010-2013)

Selected Publications

  • Reilly, D.D. Molecular Forensics Science Analysis of Nuclear Materials. Chemistry, Thesis – 2012. University of Nevada Las Vegas, Las Vegas.  http://digitalscholarship.unlv.edu/thesesdisertations/1770/
  • Tamasi, A.; Reilly, D. Oxidation and Hydration of U3O8 Materials Following Controlled Exposure to Temperature and Humidity. Analytical Chemistry. In review.
  • Conradson, S.; Batuk, O.; Reilly, D. Multiscale Speciation of U and Pu at Chernobyl, Hanford, Los Alamos, McGuire AFB, Mayak, and Rocky Flats. ES&T. In review.
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