Technology for reprocessing mother liquor and washing solution from crystalization purification of HTGR SNF

The extractants diphenyl-N,N-dioctylcarbamoylmethylphosphine oxide and diphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide for the processing of spent fuel were tested. The conditions for extraction and separation of uranium and TPE–REE were determined. A technological scheme was proposed for processing spent nuclear fuel from high-temperature gas-cooled reactors. During dynamic testing, at least 99.9% of uranium and plutonium and at least 99.5% of americium and rare earth elements were extracted. The TPE + REE and U+Pu fractions were isolated. The U+Pu fraction contained approximately 5% Am, while the TPE + REE fraction had less than 0.1% U and Pu.