Water desorption by thermo-gravimetric analysisFunded under: JRC-ENVPROT 6C
In order to prevent the risk posed by tritiated water for operators and population exposure, various solidification and disposal options have been proposed. At the moment no material is able to achieve a degree of immobilisation that the value of the maximum release rate of 0.001 % per day of tritium as HTO is not exceeded. The aim of this work is to determine the mechanism and the amount of water released from several materials including ordinary Portland cement (OPC), modified OPC, molecular sieves and synthetic clay. Water desorption was measured by thermogravimetric and differential thermal analysis at 50 C under static air and flowing N(2) (0.5 L/min). The results were compared with the evaporation of water contained in the crucible under the same conditions. OPC and aluminium sulphate, forming ettringite confirmed by XRD analysis, seem to give the best result concerning the immobilisation of water and the release rate. In that case, the release rate was one order of magnitude less than the value measured previously for OPC at about 30 C.
Bibliographic Reference: EUR 15703 EN (1994) 47 pp., free of charge
Availability: Available from Joint Research Centre, Publication Department, I-21020 Ispra (Va.) (IT)
Record Number: 199410700 / Last updated on: 1995-03-21
Original language: en
Available languages: en