Post-doc position: Release and capture of hazardous radionuclides from LBE

MYRRHA is a accelerator driven fast spectrum research reactor which will replace the current BR2 reactor at SCK-CEN. MYRRHA is conceived as a demonstrator for the Lead Cooled Fast Reactor which is one of the Generation IV reactor concepts. This class of nuclear systems is highly economical, has enhanced safety, produces minimal waste and is proliferation friendly. Furthermore an accelerator driven system like MYRRHA with the core in sub-critical mode can be used to transmute transuranic elements thereby significantly lowering the burden on the deep geological storage. To large extent, these benefits are a consequence of the coolant used in MYRRHA: liquid lead-bismuth eutectic (LBE). LBE provides an excellent radiation shield, it allows reactor operation at atmospheric pressure and ensures the conditions for a highly efficient use of nuclear fuel.

Description

To ensure safe operation of the MYRRHA reactor it is essential to minimize the impact of these radiotoxic volatiles. Several nuclides are of concern because they present an unfavorable combination of concentration, radiotoxicity and volatility. Cd, Te, Se, Os, Ru, I, Br, Cs, Rb and Tl may form a substantial hazard in an ADS system. Current knowledge about the behavior of these elements in LBE is limited.

The primary objective of this PhD is to quantitatively understand the physicochemical processes involved in the release of hazardous radionuclides from LBE. In a later stage strategies to permanently immobilize these volatiles have to be proposed and developed, within the boundary conditions of the MYRRHA reactor design.

This PhD is mainly experimental and will be conducted at SCK-CEN in either the new heavy metals lab for work with inactive material or in the contolled area for active experiments. Several setups and expertise to study the release of volatiles from LBE are already available. On that basis, new methods and if necessary instrumentation have to be developed and built for each specific element. This challenging work will require intensive use of (radio)analytical methods and detection techniques.

The PhD thesis is part of the R&D programme on volatilization and capture of hazardous radionuclides within the MYRRHA project and is embedded in a European project on safety related chemistry of heavy liquid metal reactors. Scientific stays abroad are possible through collaborations with interational partners such as the Institute for Transuranium Elements in Karlsruhe.

Nr of positions available : 1