Processing and Characterization of Sol-Gel Cerium Oxide Microspheres

Technical Report · Tue Sep 27 04:00:00 EDT 2016

DOI:https://doi.org/10.2172/1342344· OSTI ID:1342344

McClure, Zachary D. ^[1]; Padilla Cintron, Cristina ^[1]

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1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Of interest to space exploration and power generation, Radioisotope Thermoelectric Generators (RTGs) can provide long-term power to remote electronic systems without the need for refueling or replacement. Plutonium-238 (Pu-238) remains one of the more promising materials for thermoelectric power generation due to its high power density, long half-life, and low gamma emissions. Traditional methods for processing Pu-238 include ball milling irregular precipitated powders before pressing and sintering into a dense pellet. The resulting submicron particulates of Pu-238 quickly accumulate and contaminate glove boxes. An alternative and dust-free method for Pu-238 processing is internal gelation via sol-gel techniques. Sol-gel methodology creates monodisperse and uniform microspheres that can be packed and pressed into a pellet. For this study cerium oxide microspheres were produced as a surrogate to Pu-238. The similar electronic orbitals between cerium and plutonium make cerium an ideal choice for non-radioactive work. Before the microspheres can be sintered and pressed they must be washed to remove the processing oil and any unreacted substituents. An investigation was performed on the washing step to find an appropriate wash solution that reduced waste and flammable risk. Cerium oxide microspheres were processed, washed, and characterized to determine the effectiveness of the new wash solution.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1342344
• Report Number(s): PNNL--25863
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM
CERIUM OXIDES
GELATION
GLOVEBOXES
MICROSPHERES
PLUTONIUM
PLUTONIUM 238
POWER GENERATION
SINTERING
SOL-GEL PROCESS
THERMOELECTRIC GENERATORS
WASHING