Fabrication of 3D-printed PLA filter with immobilized Prussian blue for aqueous cesium removal

Abstract

This study explores a method to immobilize Prussian blue (PB) on a 3D-printed filter made of polylactic acid (PLA) to selectively remove cesium (Cs) ions from water. A pristine 3D-printed filter made of PLAwas prepared by the fused deposition modeling (FDM) based 3D printer. The surface of the pristine PLA filter was activated through a hydrolysis reaction (in sodium hydroxide solution; PLA-OH) and grafting polymerization of acrylic acid (PLA-OH/AA) to introduce hydrophilic functional groups on the PLA filter surface. This surface modification process, believed to be beneficial for forming stable PB particles, was analyzed using various characterization methods, such as Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. Furthermore, PB was immobilized in the presence of the surface-modified filter (PLA-OH54/AA), and its Cs adsorption behavior was investigated. The maximum adsorption capacity (qm) obtained using the Langmuir isotherm model was 3.67mg/g, and the adsorption kinetic was well interpreted by the pseudo-second-order model. Moreover, the column test results indicated the effective continuous Cs removal by the prepared PB-immobilized 3D filter (PLA-OH54/AA-PB). The potential of the prepared PLA-OH54/AA-PB filter as a 3D filter-type adsorbent for decontaminating radioactive Cs was demonstrated herein.