High level wastes (HLW) arising from reprocessing of pressurised heavy water reactor (PHWR) fuels contain actinides like neptunium, americium and cerium which are not extracted in the Purex 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 (phenyl)-N, N-diisobutylcarbamoylmethylphosphine oxide (CMPO) were taken up as a follow-up of successful runs with simulated sulphate bearing low acid HLW solutions. The simulated HLW arising 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. (author). 13 refs., 2 tabs., 12 figs.
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;  Badheka, L P; Banerji, A 
- Bhabha Atomic Research Centre, Bombay (India). Process Engineering and Systems Development Div.
- Bhabha Atomic Research Centre, Bombay (India). Fuel Reprocessing Group
- Bhabha Atomic Research Centre, Bombay (India). Radiochemistry Div.
- Bhabha Atomic Research Centre, Bombay (India). Bio-organic Div.