Evaluation of various carbon blacks and dispersing agents for use in the preparation of uranium microspheres with carbon

Journal Article · Thu Oct 12 00:00:00 EDT 2017 · Journal of Nuclear Materials

DOI:https://doi.org/10.1016/j.jnucmat.2017.10.033· OSTI ID:1423096

Hunt, Rodney Dale ^[1]; Johnson, Jared A. ^[1]; Collins, Jack Lee ^[1]; McMurray, Jake W. ^[1]; Reif, Tyler J. ^[1]; Brown, Daniel R. ^[2]

---

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2. X-energy, LLC, Greenbelt, MD (United States)

A comparison study on carbon blacks and dispersing agents was performed to determine their impacts on the final properties of uranium fuel kernels with carbon. The main target compositions in this internal gelation study were 10 and 20 mol % uranium dicarbide (UC₂), which is UC_1.86, with the balance uranium dioxide. After heat treatment at 1900 K in flowing carbon monoxide in argon for 12 h, the density of the kernels produced using a X-energy proprietary carbon suspension, which is commercially available, ranged from 96% to 100% of theoretical density (TD), with full conversion of UC to UC₂ at both carbon concentrations. However, higher carbon concentrations such as a 2.5 mol ratio of carbon to uranium in the feed solutions failed to produce gel spheres with the proprietary carbon suspension. The kernels using our former baseline of Mogul L carbon black and Tamol SN were 90–92% of TD with full conversion of UC to UC₂ at a variety of carbon levels. Raven 5000 carbon black and Tamol SN were used to produce 10 mol % UC2 kernels with 95% of TD. However, an increase in the Raven 5000 concentration led to a kernel density below 90% of TD. Raven 3500 carbon black and Tamol SN were used to make very dense kernels without complete conversion to UC₂. Lastly, the selection of the carbon black and dispersing agent is highly dependent on the desired final properties of the target kernels.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1423096
• Alternate ID(s): OSTI ID: 1549489
• Journal Information: Journal of Nuclear Materials, Vol. 498; ISSN 0022-3115
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
Internal gelation
Uranium microspheres
Carbon black
Dispersing agent