Alternative TRUEX-Based Pretreatment Processing of INEEL Sodium Bearing Waste

Alkaline Leaching of Key, Non-Radioactive Components from Simulants and Hanford Tank Sludge 241-S-110: Results of FY01 Studies

“…Recent work from this laboratory has shown that the presence of relatively low (10 mM or less) concentrations of low-molecular-weight compounds containing a thiol group, such as the amino acid cysteine, are extremely effective under acidic conditions at preventing the extraction of mercury by octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxides (CMPOs) or crown ether extractants over a broad range of acidic conditions (Rapko et al 2000). However, it is well known that the thiol group, RSH, is readily oxidized in neutral to alkaline solutions to form disulfides (Smith and March 2001), RS-SR, so the stability of such complexes under alkaline processing conditions is problematic.…”