Ab initio study of the trapping of polonium on noble metals

Abstract

In the future MYRRHA reactor, lead bismuth eutectic (LBE) will be used both as coolant and as spallation target. Due to the high neutron flux a small fraction of the bismuth will transmute to radiotoxic 210 Po. Part of this radiotoxic element will evaporate into the gas above the coolant. Extracting it from the gas phase is necessary to ensure a safe handling of the reactor. An issue in the development of suitable filters is the lack of accurate knowledge on the chemical interaction between a candidate filter material and either elemental polonium or polonium containing molecules. Experimental work on this topic is complicated by the high radiotoxicity of polonium. Therefore, we present in this paper a first-principles study on the adsorption of polonium on noble metals as filter

Removal of the Homolog Tellurium of Polonium by SiO2 Nanofiber Filter for Lead Alloy-Cooled Reactors

“…Based on thermal chromatography experiments, a high adhesion affinity of polonium was achieved using noble metals (Au, Ag, Pt, and Pd) and 316L stainless steel, as reported by Maugeri et al [19][20][21]. Meanwhile, the adhesion energies of Po, Po 2 , PbPo, PbBi, H 2 Po, and PoOH on noble metals were calculated by using the density functional theory (DFT) for 210 Po trapping [22][23][24]. However, the high price of noble metals limits its large-scale application for polonium removal.…”

The LBE Coolant Chemistry R&D Programme for the MYRRHA ADS: Chemistry and Control of Oxygen, Corrosion and Spallation Products

“…Recent important results obtained in collaboration with PSI include the characterization of adsorption (sticking) of polonium-bearing vapor molecules on surfaces, and the derivation of the corresponding thermochemical interaction properties. Concurrently, ab initio studies of the interaction of polonium with LBE and metal surfaces have been performed [33,34]. The latter results are used in safety studies to assess transport of polonium vapors, after their release from LBE, in various components of MYRRHA such as the proton beam tube.…”