Comparative analysis of cesium removal by coagulants, turbidity-inducing materials, and Prussian blue

Cesium (Cs) contamination in water, particularly after nuclear incidents, poses significant environmental and health risks. This study aimed to evaluate and compare the effectiveness of various coagulants—alum, ferric chloride (FeCl3), poly aluminum chloride (PAC), and poly aluminum hydroxide chloride silicate (PACl)—with and without turbidity-inducing materials, as well as the Cs removal efficiency of Prussian blue (PB). Laboratory-scale jar tests were conducted using raw water spiked with Cs-133 and analyzed using ICP-MS. FeCl3 achieved the highest removal among coagulants (13.5%), while turbidity-inducing materials increased Cs removal to 37% due to increased particle-mediated adsorption and flocculation. PB demonstrated the highest efficiency (>99.9% removal at 10 mg/L), although its combination with PACl did not further enhance removal. These findings confirm PB as the most promising adsorbent for Cs removal and show that turbidity-enhancing strategies can improve coagulation outcomes. Further optimization of PB handling, immobilization, and large-scale implementation is needed to ensure safe and practical adoption in water treatment facilities.