Skip to main content
SpringerLink
Log in

Effects of a pressurized water treatment on internal gelation sol–gel microspheres

  • Original Paper: Fundamentals of sol-gel and hybrid materials processing
  • Published:
Journal of Sol-Gel Science and Technology Aims and scope Submit manuscript

Abstract

Based on previous observations that a pressurized water treatment (PWT) prevented cracking of sol–gel microspheres, we investigated the effects of a PWT on microsphere crystallinity, density, and specific surface area (SSA). Results were used to determine how a PWT alters the properties of microspheres upon drying and heating. Microspheres with diameters near 100–200 µm were prepared with and without a PWT and measured using x-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption (BET), and pycnometry. Properties of air-dried microspheres processed with and without a PWT are compared. In addition, the properties of microspheres processed using a PWT are reported after heating to 150, 450, 750, 1050, and 1350 °C. XRD measurements indicate that the PWT step improves the crystallinity of air-dried microspheres. XRD data were also used to calculate crystallite size, which increases with higher heat-treatment temperatures. TEM images support crystallite size calculations from XRD data and provide an indication of the range of crystallite sizes, particularly for samples processed at higher temperatures where crystallite sizes are too large for estimation using the Scherrer formula. Density and SSA measurements performed as a function of heat-treatment temperature indicate that a PWT increases the density of air-dried microspheres, creates a pore network, and that significant densification occurs between 450 and 750 °C. These results may be used to inform decisions on internal gelation flowsheet parameters to optimize the microsphere formation and gelation step, prevent microsphere cracking, and produce microspheres suitable for subsequent coating operations or pressing into pellets.

Highlights

  • A PWT prevents microsphere cracking by removing impurities prior to heating.

  • Volatile species evolve from microspheres during heating prior to pore closure.

  • A PWT causes crystallite growth and a pore network to form in sol–gel microspheres.

  • A PWT step enables a wider range of acceptable sol–gel feed solution parameters.

  • Microspheres prepared using a PWT have higher density and SSA.

  • Microspheres subjected to a PWT did not agglomerate during sintering.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

Data availability

Data that support the findings of this study are available from the corresponding author upon reasonable request and subject to institutional review. Materials produced and analyzed are no longer available.

References

  1. Carmack WJ, Richardson WC, Husser DL, Mohr TC (2004) Internal gelation as applied to the production of uranium nitride space nuclear fuel. AIP Conf Proc 699:420–425. https://doi.org/10.1063/1.1649601

    Article  CAS  Google Scholar 

  2. Hunt RD, McMurray JW, Helmreich GW et al. (2020) Production of 28μm zirconium carbide kernels using the internal gelation process and microfluidics. J Nucl Mater 528:151870. https://doi.org/10.1016/j.jnucmat.2019.151870

    Article  CAS  Google Scholar 

  3. Nagley SG, Barnes CM, Husser DL et al. (2010) Fabrication of uranium oxycarbide kernels for HTR fuel. Idaho National Laboratory, Idaho Falls, ID

    Google Scholar 

  4. McMurray JW, Silva CM, Helmreich GW et al. (2016) Production of low-enriched uranium nitride kernels for TRISO particle irradiation testing. Oak Ridge National Laboratory, Oak Ridge, TN

    Book  Google Scholar 

  5. Louwrier KP, Steemers T (1970) Sol-gel process development at the European Institute for Transuranium Elements, Karlsruhe, Germany. Oak Ridge National Laboratory, Gatlinburg, TN, pp 244–252

    Google Scholar 

  6. Terrani KA, Jolly BC, Harp JM (2020) Uranium nitride tristructural-isotropic fuel particle. J Nucl Mater 531:152034. https://doi.org/10.1016/j.jnucmat.2020.152034

    Article  CAS  Google Scholar 

  7. Brugghen FWVD, Noothout AJ, Hermans MEA et al. (1970) A U(VI)-process for microsphere production. In: Sol-gel processes and reactor fuel cycles. Oak Ridge National Laboratory, Gatlinburg, TN

  8. Kanij JBW, Noothout AJ, Votocek O (1973) The KEMA U(VI)-process for the production of UO2 microspheres. In: Proceedings of a Panel on Sol-Gel Process for Fuel Fabrication. International Atomic Energy Agency, Vienna

  9. Hermans MEA (1973) Status report from The Netherlands. In: Proceedings of a Panel on Sol-Gel Processes for Fuel Fabrication. International Atomic Energy Agency, Vienna, Austria, pp 33–35

  10. Collins JL (2005) Experimental methodology for determining optimum process parameters for production of hydrous metal oxides by internal gelation. Oak Ridge National Laboratory, Oak Ridge, TN

  11. Collins JL, Chi A (2009) Determination of ideal broth formulations needed to prepare hydrous cerium oxide microspheres via the internal gelation process. Oak Ridge National Laboratory, Oak Ridge, TN

  12. Collins JL, Pye SL (2008) Determination of ideal broth formulations needed to prepare hydrous aluminum oxide microspheres by the internal gelation process. Oak Ridge National Laboratory, Oak Ridge, TN

  13. Benay G, Hubert F, Modolo G (2008) Preparation of yttria-stabilized zirconia-ceria kernels as fuel precursors using internal gelation. Radiochim Acta 96:285–291. https://doi.org/10.1524/ract.2008.1489

    Article  CAS  Google Scholar 

  14. Collins JL, Watson JS (2000) Economic evaluation for the production of sorbents and catalysts derived from hydrous titanium oxide microspheres prepared by the HMTA internal gelation process. Oak Ridge National Laboratory, Oak Ridge, TN

    Google Scholar 

  15. Idemitsu K, Arima T, Inagaki Y et al. (2003) Manufacturing of zirconia microspheres doped with erbia, yttria and ceria by internal gelation process as a part of a cermet fuel. J Nucl Mater 319:31–36. https://doi.org/10.1016/S0022-3115(03)00130-2

    Article  CAS  Google Scholar 

  16. Kumar N, Pai RV, Joshi JK et al. (2006) Preparation of (U,Pu)O2 pellets through sol–gel microsphere pelletization technique. J Nucl Mater 359:69–79. https://doi.org/10.1016/j.jnucmat.2006.07.018

    Article  CAS  Google Scholar 

  17. Kumar A, Radhakrishna J, Kumar N et al. (2013) Studies on preparation of (U0.47,Pu0.53)O2 microspheres by internal gelation process. J Nucl Mater 434:162–169. https://doi.org/10.1016/j.jnucmat.2012.11.009

    Article  CAS  Google Scholar 

  18. Pai RV, Mukerjee SK, Vaidya VN (2004) Fabrication of (Th,U)O2 pellets containing 3 mol% of uranium by gel pelletisation technique. J Nucl Mater 325:159–168. https://doi.org/10.1016/j.jnucmat.2003.11.010

    Article  CAS  Google Scholar 

  19. Pai RV, Dehadraya JV, Bhattacharya S et al. (2008) Fabrication of dense (Th,U)O2 pellets through microspheres impregnation technique. J Nucl Mater 381:249–258. https://doi.org/10.1016/j.jnucmat.2008.07.044

    Article  CAS  Google Scholar 

  20. Morihira M, Nakamura M, Ozawa T et al. (2005) Final report of the FUJI Project concerning the research and development of advanced sphere-pac fuel among JNC, PSI, and NRG. Japan Nuclear Cycle Development Institute, Tokai, Japan

    Google Scholar 

  21. Ledergerber G, Ingold F, Stratton RW et al. (1996) Preparation of transuranium fuel and target materials for the transmutation of actinides by gel coconversion. Nucl Technol 114:194–204. https://doi.org/10.13182/NT96-A35249

    Article  CAS  Google Scholar 

  22. Daniels H, Neumeier S, Modolo G (2010) Synthesis of Uranium-based Microspheres for Transmutation of Minor Actinides. ACSEPT International Workshop, Lisbon, Portugal, 31 Mar - 2 Apr 2010, Commissariat a l’Energie Atomique - CEA (France)

  23. Petti D (2009) Deep-Burn: Development of Transuranic Fuel for High-Temperature Helium-Cooled Reactors. - is a 604pg report with no report number, issued by Idaho National Laboratory, Idaho Falls, ID

  24. Robisson AC, Lemonnier S, Grandjean S (2004) Sol gel chemistry applied to the synthesis of actinide-based compounds for the fabrication of advanced fuels. CEA/VALRHO, Nimes, France

  25. Katalenich JA, Hartman MR, O’Brien RC, Howe, SD (2013) Fabrication of cerium oxide and uranium oxide microspheres for space nuclear power applications. In: Nuclear and emerging technologies for space (NETS 2013), Albuquerque NM,02/25/2013,02/28/2013. Idaho National Laboratory, Idaho Falls, ID, Albuquerque, NM

  26. Burkes D, Wachs D, Werner J, Howe S (2007) An overview of current and past W-UO2 CERMET fuel fabrication technology. In: Space Nuclear Conference 2007—Proceedings of the Embedded Topical Meeting, Idaho National Laboratory, Idaho Falls, ID

  27. Hunt RD, Collins JL (2004) Uranium kernel formation via internal gelation. Radiochim Acta 92:909–915. https://doi.org/10.1524/ract.92.12.909.55110

    Article  CAS  Google Scholar 

  28. Collins JL (2004) Production of depleted UO2 kernels for the advanced gas-cooled reactor program for use in TRISO coating development. Oak Ridge National Laboratory, Oak Ridge, TN

  29. Barnes C, Richardson C, Nagley S et al. (2010) Fabrication of uranium oxycarbide kernels for HTR fuel. Idaho National Laboratory (United States). Funding organisation: DOE-NE (United States), Idaho Falls, ID

    Google Scholar 

  30. Grover SB, Petti D, and Maki J (2010) Completion of the first NGNP Advanced Gas Reactor Fuel Irradiation Experiment, AGR1, in the Advanced Test Reactor, Idaho National Laboratory, Idaho Falls, ID

  31. Phillips JA, Barnes CM, Hunn JD (2010) Fabrication and comparison of fuels for advanced gas reactor irradiation tests. In: Proceedings of the HTR, Oak Ridge National Laboratory, Oak Ridge, TN

  32. Snead LL, Terrani KA, Venneri F, et al. (2011) Fully ceramic microencapsulated fuels: a transformational technology for present and next generation reactors—properties and fabrication of FCM fuel. Trans Am Nucl Soc 104:668–670

  33. Terrani KA, Snead LL, Gehin JC (2012) Microencapsulated fuel technology for commercial light water and advanced reactor application. J Nucl Mater 427:209–224. https://doi.org/10.1016/j.jnucmat.2012.05.021

    Article  CAS  Google Scholar 

  34. Terrani K, Kiggans J, Katoh Y, et al. (2012) Fabrication and characterization of fully ceramic microencapsulated fuels. J Nucl Mater 426. https://doi.org/10.1016/j.jnucmat.2012.03.049

  35. Snead LL (2018) Method for fabrication of fully ceramic microencapsulation nuclear fuel, US Patent US10109378B2, Ultra Safe Nuclear Corp

  36. Venneri F (2015) Fully Ceramic Micro-Encapsulated (FCM) Fuel for CANDUs and other Reactors, US Patent US20150170767A1, Ultra Safe Nuclear Corp

  37. Venneri F (2019) Dispersion Ceramic Micro-encapsulated (DCM) Nuclear Fuel and Related Methods, US Patent US10475543B2, Ultra Safe Nuclear Corp

  38. Venneri F (2019) Micro Modular Reactor (MMR) Energy Systems, in proc. IFNEC Workshop, IFNEC, Warsaw, Poland

  39. Powers JJ, Worrall A, Terrani KA et al. (2014) Fully ceramic microencapsulated fuels. Characteristics and potential LWR applications. Japan Atomic Energy Agency, Tōkai, Ibaraki Prefecture, Kyoto, Japan

  40. Pappano P (2018) TRISO-X Fuel Fabrication Facility Overview, Rockville, MD - is a presentation given to the US Nuclear Regulatory Commission

  41. X-energy. Reactor: Xe-Mobile - X-energy: Nuclear Energy, Nuclear Reactors & Fuel Design. https://x-energy.com/reactors/xe-mobile. Accessed 22 Apr 2020

  42. Arafat Y (2019) Westinghouse eVinci Micro-Reactor Program, in proc. GAIN-EPRI-NEI-US NIC Micro-Reactor Workshop, Idaho Falls, ID

  43. BWX Technologies (2020) BWX Technologies-led team wins department of defense contract for mobile nuclear reactor design. https://www.bwxt.com/news/2020/03/17/BWXT-Led-Team-Wins-Department-of-Defense-Contract-for-Mobile-Nuclear-Reactor-Design. Accessed 22 Apr 2020

  44. BWX Technologies (2020) BWX Technologies Continuing TRISO Line Restart Activities with Kernel Formation and Sintering Operations. https://www.bwxt.com/news/2020/04/21/BWXT-Continuing-TRISO-Line-Restart-Activities-With-Kernel-Formation-and-Sintering-Operations. Accessed 22 Apr 2020

  45. Venneri P (2019) Overview of USNC-Tech LEU Fission Power Systems for Space Applications, in proc. Nuclear Energy in Space: Nonproliferation Risks and Solutions, Washington DC, Univ. Texas

  46. X-energy, Nuclear & Space - X-energy: Nuclear Energy, Nuclear Reactors & Fuel Design. https://x-energy.com/why/nuclear-and-space. Accessed 22 Apr 2020

  47. Lloyd MH, Bischoff K, Peng K et al. (1976) Crystal habit and phase attribution of U (VI) oxides in a gelation process. J Inorg Nucl Chem 38:1141–1147

    Article  CAS  Google Scholar 

  48. Vaidya VN, Mukherjee SK, Joshi JK et al. (1987) A study of chemical parameters of the internal gelation based sol-gel process for uranium dioxide. J Nucl Mater 148:324–331

    Article  CAS  Google Scholar 

  49. Collins JL, Lloyd MH, Fellows RL (1984) Effects of process variables on reaction mechanisms responsible for ADUN hydrolysis, precipitation, and gelation in the internal gelation gel-sphere process. Oak Ridge National Laboratory, Oak Ridge, TN

    Book  Google Scholar 

  50. Collins JL, Lloyd MH, Shell SE (2005) Control of urania crystallite size by HMTA-urea reactions in the internal gelation process for preparing (U, Pu)O2 fuel kernels. Oak Ridge National Laboratory, Oak Ridge, TN

  51. Hunt RD, Montgomery FC, Collins JL (2010) Treatment techniques to prevent cracking of amorphous microspheres made by the internal gelation process. J Nucl Mater 405:160–164. https://doi.org/10.1016/j.jnucmat.2010.08.007

    Article  CAS  Google Scholar 

  52. Katalenich JA (2020) Use of a pressurized water treatment to prevent cracking of internal gelation sol-gel microspheres. J Sol-Gel Sci Technol. https://doi.org/10.1007/s10971-020-05230-1

  53. Gao Y, Ma J, Zhao X et al. (2016) The fabrication of ZrO2–ZrC microspheres by internal gelation and carbothermal reduction process. J Am Ceram Soc 99:1184–1191. https://doi.org/10.1111/jace.14066

    Article  CAS  Google Scholar 

  54. Borland M, Frank S, Lessing P et al. (2008) Evaluation of aqueous and powder processing techniques for production of Pu-238 fueled general purpose heat sources. Idaho National Laboratory, Idaho Falls, ID

    Google Scholar 

  55. Katalenich JA (2017) Production of cerium dioxide microspheres by an internal gelation sol–gel method. J Sol-Gel Sci Technol 82. https://doi.org/10.1007/s10971-017-4345-8

  56. Katalenich JA, Kitchen BB, Pierson BD (2018) Production of monodisperse cerium oxide microspheres with diameters near 100 µm by internal-gelation sol–gel methods. J Sol-Gel Sci Technol 86:329–342. https://doi.org/10.1007/s10971-018-4641-y

    Article  CAS  Google Scholar 

  57. Katalenich JA (2019) Impurity levels in cerium oxide microspheres prepared by internal gelation sol–gel methods. J Sol-Gel Sci Technol. https://doi.org/10.1007/s10971-019-05165-2

  58. Langford JI, Wilson AJC (1978) Scherrer after sixty years: a survey and some new results in the determination of crystallite size. J Appl Crystallogr 11:102–113

    Article  CAS  Google Scholar 

  59. Tian HH, Atzmon M (1999) Comparison of X-ray analysis methods used to determine the grain size and strain in nanocrystalline materials. Philos Mag A 79:1769–1786. https://doi.org/10.1080/01418619908210391

    Article  CAS  Google Scholar 

  60. Debets PC, Loopstra BO (1963) On the uranates of ammonium—II X-ray investigation of the compounds in the system NH3-UO3-H2O. J Inorg Nucl Chem 25:945–953

    Article  CAS  Google Scholar 

  61. Bickford DF, Rankin DT (1975) Fabrication of granule and pellet heat sources from oxalate-based 238PuO2. Savannah River Laboratory, Aiken, SC

  62. Bickford DF, Rankin DT, Smith PK (1976) Preparation, microstructures, and properties of PuO2. Savannah River Laboratory, Aiken, SC, Berkeley, CA

  63. Kent RA (1979) LASL fabrication flowsheet for GPHS fuel pellets. Los Alamos Scientific Laboratory, Los Alamos, NM

    Book  Google Scholar 

  64. Ganguly C (1993) Sol-gel microsphere pelletization: a powder-free advanced process for fabrication of ceramic nuclear fuel pellets. Bull Mater Sci 16:509–522

    Article  CAS  Google Scholar 

  65. Zimmer E, Ganguly C, Borchardt J, Langen H (1988) SGMP—an advanced method for fabrication of UO2 and MOX fuel pellets. J Nucl Mater 152:169–177

    Article  Google Scholar 

  66. Suryanarayana S, Kumar N, Bamankar YR et al. (1996) Fabrication of UO2 pellets by gel pelletization technique without addition of carbon as pore former. J Nucl Mater 230:140–147

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors would like to thank Bruce Pierson of the Nuclear Engineering and Radiological Sciences Department, University of Michigan and Dr. John Halloran of the Material Science and Engineering Department, University of Michigan for their useful input and ideas regarding this work. The authors would also like to acknowledge and thank Eongyu Yi of the Material Science and Engineering Department, University of Michigan for performing nitrogen adsorption surface area analyses. TEM was performed by Xu Wang, a graduate student under Dr. Lumin Wang, of the Nuclear Engineering and Radiological Sciences Department, University of Michigan.

Funding

This research was conducted with government support under and awarded by DoD, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a. This material is based on work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE 1256260. Any opinion, findings, and conclusions or recommendations expressed in this material are that of the authors and does not necessarily reflect the views of the National Science Foundation. This material is based on the work supported by the Center for Space Nuclear Research (CSNR) under the Universities Space Research Association (USRA) Subcontract 06711-003. The USRA operates the CSNR for the Idaho National Laboratory. This research was supported by a research seed grant received from the Michigan Space Grant Consortium with matching funds from the Department of Nuclear Engineering and Radiological Sciences, University of Michigan.

Author information

Author notes

  1. Jeffrey A. Katalenich

    Present address: Pacific Northwest National Laboratory, 3230 Innovation Blvd., MSIN K8-34, Richland, WA, 99354, USA

Authors and Affiliations

  1. Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2355 Bonisteel Blvd., Ann Arbor, MI, 48109, USA

    Jeffrey A. Katalenich & Brian B. Kitchen

Authors
  1. Jeffrey A. Katalenich
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Brian B. Kitchen
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Jeffrey A. Katalenich.

Ethics declarations

Conflict of interest

The authors declare no competing interest.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Katalenich, J.A., Kitchen, B.B. Effects of a pressurized water treatment on internal gelation sol–gel microspheres. J Sol-Gel Sci Technol 98, 288–299 (2021). https://doi.org/10.1007/s10971-021-05479-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10971-021-05479-0

Keywords

Search

Navigation