Cesium ion exchange testing using crystalline silicotitanate with Hanford tank waste 241-AP-107

ABSTRACTPacific Northwest National Laboratory has been tasked with demonstrating the unit operations for the Low Activity Waste Pretreatment System with actual Hanford tank waste. Crystalline silicotitanate (CST) ion exchange media is planned to be used to remove cesium (137Cs) from the aqueous phases of the tank wastes. Washington River Protection Solutions requested that Hanford tank waste collected from tank 241-AP-107 be processed using conceived pretreatment steps (suspended solids removal by filtration, Cs removal by ion exchange), then vitrified. Removal of Cs from these wastes is an important processing step in preparing the waste for long-term safe storage. Batch contact testing was performed to find the Cs load capacity at the equilibrium feed condition. Bench-scale ion exchange testing with approximately 9 L of filtered AP-107 supernate was conducted using CST. Column testing was performed using prototypic LAWPS operations in a lead-lag column arrangement using 10-mL CST beds. Feed was processe...