(608a) Kinetic Comparisons of Cesium Ion Exchange Performance with Crystalline Silicotitanate

Crystalline silicotitanate (CST) ion exchanger is currently selected to remove cesium (¹³⁷Cs) from the aqueous phase of Hanford tank wastes. The Advanced Modular Pretreatment System (AMPS) will provide pretreatment capabilities for tank waste supernate originating from double-shell tanks in the 200 East area of the Hanford site. To optimize and evaluate exchange kinetics during AMPS cesium removal, Pacific Northwest National Laboratory conducted laboratory-scale ion exchange column tests at various residence times and scales to determine throughput rates and CST usage. Testing conditions were scaled up from laboratory to full-scale operations to assess AMPS processing conditions at the various residence times. Based on these results, a determination of mass transfer coefficients as well as tradeoffs of CST usage with flowrate were conducted. Data presented will allow for future modeling of breakthrough performance at a range of processing conditions necessary for AMPS flowsheet development.