Understanding and exploiting crystal formation during sodium chloride crystallization on 3D-printed mesh materials

Abstract

Though crystallization is one of the oldest separation and purification processes, understanding and controlling it can be challenging. In this study, 3D-printed meshes were developed and tested for sodium chloride (NaCl) crystallization in two different configurations: one involving a stagnant NaCl solution and one using a flow-through crystallizer. Experiments with the stagnant NaCl solution investigated the effect of the coverage of the 3D-printed meshes and the roughness on solid salt recovery and size, while the flow-through crystallizer testing investigated the effect of solution/air interfaces in contact with the mesh on solid salt recovery and size. Higher solid salt recoveries were achieved for a mesh with a coverage of 52.24% and by increasing the solution/air interfaces in contact with the meshes; roughness changes did not have any significant effect on solid salt recovery. Finally, a potential mechanism explaining the salt formation from the solution/air interface towards the non-immersed portion of the mesh was developed.