Optimization of TRPO process parameters for americium extraction from high level waste

The numerical calculations for Am multistage fractional extraction by trialkyl phosphine oxide (TAPO) were verified by a hot test. 1750 L/t-U high level waste (HLW) was used as the feed to the TFPO process. The analysis used the simple objective function to minimize the total waste content in the TFPO process streams. Some process parameters were optimized after other parameters were selected. The optimal process parameters for Am extraction by TFPO are: 10 stages for extraction and 2 stages for scrubbing; a flow rate ratio of 0.931 for extraction and 4.42 for scrubbing; nitric acid corcentration of 1.35 mol/L for the feed and 0.5 mol/L for the scrubbing solution. Finally, the nitric acid and Am corcentration profiles in the optimal TRPO extraction process are given.