JRP CALL information
Supported By

European Commission

Short description of the work

This project is focused on the comparative study of Pu(IV) intrinsic colloids obtained by sonolysis of PuO2 in pure water and by hydrolysis of Pu(IV) nitric acid solutions. Ultrasonic treatment of PuO2 calcined at 520°C (SBET=13.6 m2•g-1) and 600°C (SBET=13.3 m2•g-1) in contact with air for 12h has been performed using 20 kHz ultrasound at the acoustic power of 0.34W•mL-1 in pure water saturated with argon or Ar/10%CO. Temperature of 25°C inside the sonoreactor during sonolysis was controlled by a cryostat. The reactor was installed in the hot glove box at ATALANTE research facility. Hydrolytic Pu(IV) colloids were prepared by the dilution of concentrated Pu(IV) nitric solutions in pure water. The obtained colloids have been characterized by UV/Vis, SEM and XAFS spectroscopy. XAFS measurements at Pu L3 edge (XANES and EXAFS), have been performed at ROBL beamline (ESRF Grenoble). Soft NEXAFS spectrum and STXM measurements have been performed at MES Beamline 11-0-2 (ALS Berkeley) to probe plutonium N4,5 edges. The samples of Pu colloids have been sent to JRC-ITU for HRTEM analysis. The preliminary TEM analysis confirmed the STXM data that sonochemical colloid is composed of 20-30 round shaped nanoparticles. Further HRTEM study will be performed in 2015 to identify the atomic structure of both, sonochemical and hydrolytic colloids.

Main visitor contact data
Name: Dr. Sergey Nikitenko
Organisation: ICSM

JRP Identification
JRP nr: TALI-C02-01
JRP title: Preparation and study of Pu(IV) nanoparticles in solutions
JRP scope: Scope 1: Actinide separation chemistry

Visited Associated Pooled Facility
Visited APF during the stay: JRC-ITU - Labs & Hot-cells
Name of the APF Contact Person: Thierry Wiss

Other APF and organisation involved in the JRP
Other organisations involved: LBNL, Berkeley, USA (David Shuh)
Other APF involved in the project: CEA - ATALANTE, HZDR - ROBL

Description of the work done at the associated pooled facility
Start date of the stay: 6/25/2014
End date of the stay: 6/26/2014
Quantity of access: 2
Access Unit: Days