Waste simulated

Behrens, E. A., Sylvester, P., Clearfield, A., Assessment of a Sodium Monotitanate and Pharmacosiderite-Type Ion Exchangers for Strontium and Cesium Removal from DOE Waste Simulants, Environ. Sci. Technol. 32, 101-107 (1998). 

Some of the modifiers in this study (1-5) were also evaluated in the isoparaffinic diluent Isopar L for cesium extraction performance from a Savannah River waste simulant. The effect the modifiers have on the cesium distribution ratio in aliphatic diluents is more pronounced than it is in polar diluents, such as 1,2-DCE, previously used. The cesium distribution results are shown in Table 4.17 alongside those obtained from 1 M NaN03 in 1,2-DCE. 

The observed trend in DCs obtained from the alkaline waste simulant by solvents using Isopar L diluent is the same as that observed from 1 M sodium nitrate using... 

The CSSX process flowsheet for the decontamination of high-level waste was demonstrated in a 33-stage, 2-cm contactor apparatus at the Savannah River National Laboratory (formerly the Savannah River Technology Center).107 Simulated SRS average waste, simulated Tank 37H/44F composite waste, and actual Tank 37H/44F composite high-level waste were processed in three tests lasting 6,12, and 48 hours, respectively. 

Although solvent samples have been observed for approximately one year without any solids formation, work was completed to define a new solvent composition that was thermodynamically stable with respect to solids formation and to expand the operating temperature with respect to third-phase formation.109 Chemical and physical data as a function of solvent component concentrations were collected. The data included BC6 solubility cesium distribution ratio under extraction, scrub, and strip conditions flowsheet robustness temperature range of third-phase formation dispersion numbers for the solvent against waste simulant, scrub and strip acids, and sodium hydroxide wash solutions solvent density viscosity and surface and interfacial tension. These data were mapped against a set of predefined performance criteria. The composition of 0.007 M BC6, 0.75 M l-(2,2,3,3-tetrafluoropropoxy)-3-(4-.sw-butylphenoxy)-2-propanol, and 0.003 M TOA in the diluent Isopar L provided the best match between the measured properties and the performance criteria. 

All solvent components have very high partition ratios, as demonstrated on average SRS waste simulant [49-51], The annual processing losses estimated from partition data under the SRS conditions were <4% of BOBCalixC6, <27% Cs-7SB, and <9% of TOA [49], These values are upper limits, because the partition ratios were higher than could be accurately measured. Thus, there is no basis to believe that reagent loss by partitioning to the aqueous phase poses an issue in normal applications (e.g., SRS and Hanford). 

Delmau, L. H., Haverlock, T. J., Sloop, F. V., Jr., and Moyer, B. A. Caustic-Side Solvent Extraction, Prediction of Cesium Extraction from Actual Wastes and Actual Waste Simulants, Report ORNL TM-2003/011, Oak Ridge National laboratory, Oak Ridge, TN, February 2003. 

These waste simulation trials based on laboratory column experiments still needed to be validated using a field approach. Two field leaching tests were thus built on an experimental site (CERED, Vernon, France) to simulate real conditions of a waste deposit site receiving rain or run-off water (Perrodin et al., 2002). The first... 

Radiocesium is a significant issue as a part of the DOE clean-up effort Selective sequestration of cesium has been addressed by polymer-bound crown ethers e.g. the SuperLig 644) and the crystalline silicotitanates. While both of these methods are effective, they each have their drawbacks. By lining the pores of SAMMS with ferrocyanide complexes, it is possible to remove all the cesium from waste simulant solutions in a matter of minutes [12]. This sorbent is not... 

Figure 26 Pertechnetate distribution ratios versus the weight percent PEG-2000 in the stock solution contacted with three Hanford tank waste simulants to form an ABS. The simulated waste formulations are given in Ref. 51.

Figure 28 Dws for pertechnetate uptake from three Hanford tank waste simulants versus the molecular weight of the grafted polymer for four ABEC resins.

Figure 7. Detection of Cs in a tank waste simulant (pH 14) with and without Cs ions. The noise in the response can be reduced by using cantilevers of inert...

---