Estimation of Carbon-14 in the graphite reflector of research reactor

Cirus was a 40 MWt thermal research reactor, permanently shutdown in 2010. The reactor vessel is surrounded by annular graphite reflector to improve the neutron economy. The reactor pile structure material including graphite reflector, is exposed to neutron flux during the reactor operation and is subjected to activation. It is necessary to determine the radiological characteristics of the core structural material, in order to plan for future decommissioning of the reactor. The irradiated graphite reflector is expected to contain significant amount of the isotope ¹⁴C. Estimation of ¹⁴C is essential for waste management. A method to extract carbon in liquid phase which is chemically suitable for liquid scintillation counting is discussed. A sample collected from inner graphite reflector is processed using this method and amount of ¹⁴C is estimate