Development of a device for producing multi-material microspherical gels

Marufuji, Takato; Ueta, Shohei; Kawaguchi, Koichi; Watanabe, Masashi; Yan, X.

JAEA-Technology 2026-011, 22 Pages, 2026/08

JAEA-Technology-2026-011.pdf:1.84MB

In microcapsule production employing a novel double-layer coating technique in which the fuel core is pre-sealed, the required droplet size is larger than that in conventional methods, necessitating a re-examination of the optimal manufacturing conditions. However, conventional equipment involves multiple operating parameters that vary simultaneously, making it difficult to isolate and evaluate the effect of each parameter and thus hindering the identification of optimal conditions. In addition, the economic performance of the equipment is an important issue for practical application. To address these challenges, this study developed a new apparatus that enables independent control and evaluation of each parameter while also reducing cost.

Stabilization of post-experiment nuclear materials in Plutonium Fuel Research Facility

Sato, Takumi; Otobe, Haruyoshi; Morishita, Kazuki; Marufuji, Takato; Ishikawa, Takashi; Fujishima, Tadatsune; Nakano, Tomoyuki

JAEA-Technology 2023-016, 41 Pages, 2023/09

JAEA-Technology-2023-016.pdf:2.74MB

This report summarizes the results of the stabilization treatments of post-experiment nuclear materials in Plutonium Fuel Research Facility (PFRF) from August 2018 to March 2021. Based on the management standards for nuclear materials enacted after the contamination accident that occurred at PFRF on June 6, 2017, the post-experiment nuclear materials containing plutonium (Pu): samples mixed with organic substances that cause an increase in internal pressure due to radiolysis (including X-ray diffraction samples mixed with epoxy resin and plutonium powder which caused contamination accidents), carbides and nitrides samples which is reactive in air, and chloride samples which may cause corrosion of storage containers, were selected as targets of the stabilization. The samples containing organic materials, carbides and nitrides were heated in an air flow at 650 C and 950 C for 2 hours respectively to remove organic materials and convert uranium (U) and Pu into oxides. U and Pu chlorides in LiCl-KCl eutectic melt were reduced and extracted into liquid Cd metal by a reaction with lithium (Li) -cadmium (Cd) alloy and converted to U-Pu-Cd alloy at 500 C or higher. All of the samples were stabilized and stored at PFRF. We hope that the contents of this report will be utilized to consider methods for stabilizing post experiment nuclear materials at other nuclear fuel material usage facilities.

Research on the production of heterogeneous material micro gel spheres

Kawaguchi, Koichi; Ueta, Shohei; Marufuji, Takato; Yan, X.

no journal, , 

Functional microcapsules, which have more economical and efficient R&D needs than before, have been developed in a variety of fields in a new manufacturing method to miniaturize from microclocles to nano-levels. In order to apply the conventional dolgel method to microcapsules using a different material nanogenic film, the simultaneous control of the two different slugel reaction process is an issue. On the other hand, liposomes, which are emulsion, may be able to form a very thin hydrolysis reaction at the interface by lipping lipid double layer and hydrophobic hydration associated with heating. Authors tried to manufacture a double gel sphere consisting of neodimium hidrate and zirconium hidrate by dripping THMA and neodimium nitrate aqueous solution into heated two phases of the DoPC pentadecane solution and the zirconium nitrate aqueous solution. This work was supported by JSPS KAKENHI Grant Number JP23K04562.