Precise radiocarbon determination in radioactive waste by a laser-based spectroscopic technique

The precise and accurate determination of the radionuclide inventory in radioactive waste streams, including those generated during nuclear decommissioning, is a key aspect in establishing the best suited nuclear waste management and disposal options. Radiocarbon is playing a crucial role in this scenario because it is one of the so called difficult-to-measure isotopes; currently 14-C analysis requires complex systems, such as Accelerator Mass Spectrometry (AMS) or Liquid Scintillation Counting (LSC). In this paper, we demonstrate that the laser-based Saturated-Absorption Cavity Ring-down (SCAR) spectroscopic technique has several distinct advantages and represents a mature and accurate alternative for 14-C content determination in nuclear waste. As a proof-of-principle experiment, we show consistent results of AMS and SCAR for samples of concrete and graphite originating from nuclear installations. In particular, we determined mole fractions of 1.312(9) F14C and 30.951(7) F14C, respectively, for two different graphite samples originating from different regions of the Adiabatic Resonance Crossing activator prototype installed on one irradiation line of a MC40 Scanditronix cyclotron. Moreover, a mole fraction of 0.593(7) F14C from a concrete sample originating from an external wall of the Ispra-1 nuclear research reactor currently in the decommissioning phase.

DELLI SANTI Maria Giulia;  INSERO Giacomo;  BARTALINI Saverio;  CANCIO Pablo;  CARCIONE Federico;  GALLI Iacopo;  GIUSFREDI Giovanni;  MAZZOTTI Davide;  BULGHERONI Antonio;  MARTINEZ FERRI Ana;  ALVAREZ SARANDES LAVANDERA Rafael;  ALDAVE DE LAS HERAS Laura;  RONDINELLA Vincenzo;  DE NATALE Paolo; 

2022-10-24

NATL ACAD SCIENCES

JRC127117

0027-8424 (online),   

https://www.pnas.org/doi/full/10.1073/pnas.2122122119,    https://publications.jrc.ec.europa.eu/repository/handle/JRC127117,   

10.1073/pnas.2122122119 (online),