High level wastes (HLW) arising from reprocessing of pressurised heavy water reactor (PHWR) fuels contain actinides like
neptunium, americium and curium which are not extracted in the Pure:< process. They also contain small quantities of uranium and plutonium in addition to fission products. Removal of these actinides prior to vitrification of HLW can effectively reduce the active surveillance period of final waste form. Counter current studies using indigenously synthesised octyl (phonyl)-N, N-diisobutylcarbamoylmethylphosphine oxide <CMP0) were taken up as a follow up of successful runs with simulated sulphate bearing low acid HLW solutions. The simulated HLW arsing from reprocessing of PHWR fuel was prepared based on presumed burnup of 6500 MWd/Te of uranium, 3 years cooling period and 800 litres of waste generation per tonne of fuel reprocessed. The alpha activity of the HLW raffinate after extraction with the CMPO - TBP mixture could be brought down to near background level.
A. Banerji, Deshingkar, D. S., Chitnis, R. R., Wattal, P. K., Theyyunni, T. K., Nair, M. K. T., Ramanujam, A., Dhami, P. S., Gopalakrishnan, V., Rao, M. K., Mathur, J. N., Murali, M. S., Iyer, R. H., and Badheka, L. P., “Partitioning of actinides from Stimulated high level waste arising from reprocessing of PHWR fuels: Counter Current extracts on studies using CMPO”, Bhabha Atomic Research Centre, Bombay, BARC/1994/E/014, 1994.