The Chemical Kinetics of Alkaline Extraction of Tellurium from Lead-Bismuth Eutectic

• Published in: Journal of nuclear science and technology Vol. 42; no. 7; pp. 618 - 625
• Main Authors: AUMAN, Laurence E., LOEWEN, Eric P., GESELL, Thomas F., OHNO, Shuji
• Format: Journal Article
• Language: English
• Published: Tokyo Taylor & Francis Group 01.07.2005; Atomic Energy Society of Japan
• Subjects: alkaline extraction; Applied sciences; Arrhenius rate law; chemical kinetics; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Installations for energy generation and conversion: thermal and electrical energy; lead-bismuth eutectic; polonium; tellurium; polonium; Nuclear engineering; lead-bismuth eutectic; Chemical reaction kinetics; Tellurium; chemical kinetics; Eutectic; Bismuth; Lead; Extraction; Polonium 210; Arrhenius rate law; alkaline extraction
• ISSN: 0022-3131; 1881-1248
• DOI: 10.1080/18811248.2004.9726429

Developing the technology to remove neutron activation products from lead-bismuth eutectic requires understanding the chemical kinetics of the removal reaction. Polonium-210, an important radioactive product caused by neutron activation of lead-bismuth eutectic, poses a radiological hazard if a system breach occurred or system maintenance is performed. Methods to remove 210 Po have been discussed in the literature. One approach under consideration is to develop a system that would chemically remove 210 Po. The removal method under investigation in this research is alkaline extraction. Chemical kinetic measurements were made to determine first and second order rate constants and the activation energy at various temperatures using tellurium as a surrogate. First and second order alkaline extraction rate constants were measured to be: k 1 =2.17e -40,483 / RT and k 2 =8.18e -74,018 / RT where R is the ideal gas constant and T is the temperature in degrees Kelvin. Alkaline extraction is dependent on temperature and was found to follow the Arrhenius rate law. The activation energy (E a ) ranged between 40,483-74,018 J·mol -1 . With a strong foundation of surrogate work completed, this work should be validated using 210 Po.