Thermochemical safety evaluation of tertiary pyridine resin for the application to multi-functional reprocessing process “Adv.-ORIENT cycle development”

• Published in: Progress in nuclear energy (New series) 2011-09, Vol.53 (7), p.988-993
• Main Authors: Sato, Yoshihiko, Okada, Ken, Akiyoshi, Miyako, Matsunaga, Takehiro, Koyama, Shin-ichi, Suzuki, Tatsuya, Ozawa, Masaki
• Format: Article
• Language: English
• Subjects: Adv.-ORIENT cycle; Applied sciences; Energy; Energy. Thermal use of fuels; Evaporation; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fuels; Preparation and processing of nuclear fuels; Tertiary pyridine resin; Thermochemical safety
• ISSN: 0149-1970
• DOI: 10.1016/j.pnucene.2011.04.015

As part of “Adv.-ORIENT” ( Advanced Optimization by Recycling Instructive Eleme NTs) cycle technologies, which aim to develop a new fuel cycle based on a fast reactor cycle system, the reactivity between a tertiary pyridine resin (TPR) and a methanol-nitric acid solution at elevated temperatures has been investigated in order to prevent runaway reactions. The influence of metal ions, which simulate metallic elements in nuclear spent fuels, and that of the composition of the methanol-nitric acid solution, on the thermal hazards of the mixture of TPR and the methanol-nitric acid solution has been estimated through thermal analysis and gram-scale heating experiments. Simulated high level liquid waste nitric acid solutions (SHLLW) were prepared through the addition of 28 reagents. It is reasonable to consider that metal ions have little influence on the thermal stability of the TPR-methanol-nitric acid system. However, it is likely that the possibility of thermal explosion is increased because the heat of the reaction of the TPR-methanol-SHLLW system with its precipitates is largest in all samples. It is reasonable to assume that the vigorous reactions of the TPR-methanol-nitric acid or SHLLW system would occur minimally in a closed and reflux condition even if this system were heated, because the exothermic reaction of the TPR-methanol-nitric acid or SHLLW system would be prevented by the latent heat of the evaporation of methanol-nitric acid solution. ► The reactivity of a tertiary pyridine resin (TPR) was investigated. ► The influence of metal ions was estimated. ► And the influence of the composition of the methanol-HNO 3 solution was estimated. ► Metal ions have little influence on the thermal stability of the TPR system. ► The vigorous reactions would occur minimally in a closed and reflux condition.