Roll-to-roll production of a cellulose filter with immobilized Prussian blue for ¹³⁷Cs adsorption

Nuclear power plant accidents can release radioactive cesium in the water and, thus, proper removal technologies are required. Since Prussian blue can selectively adsorb Cs, studies to attach it onto supporting materials such as activated carbon and filters have been conducted. Here, we propose a roll-to-roll method for fabricating cellulose filters with immobilized Prussian blue easily and in large quantities; the physical properties and Cs adsorption performance of these filters were similar to their counterparts prepared in a conventional batch reactor. We performed batch and continuous filtration experiments to confirm their decontamination performance for radioactive cesium with 300 Bq/L of initial concentration. In the batch test, an adsorbent dosage of 0.05 g/L enabled a >95 % decontamination in 24 h; the continuous filtration experiment revealed that a 95 % decontamination was kept for up to 10 h. The proposed roll-to-roll method could allow the production of several filters for the effective removal of cesium from the water.