Oiling-Out Investigation And Morphology Control Of Beta-Alanine Based On Ternary Phase Diagrams

Crystallization is widely utilized as a purification technique in industries. Frequently in the course of crystallization, oiling-out, or termed liquid liquid phase separation (LLPS), occurs and strongly influences the morphology of crystals. To research how to control and optimize the crystal habits when there is oiling-out, we investigated' the beta-alanine water isopropanol ternary system. Four ternary phase diagrams at 25, 30, 35, and 40 degrees C were constructed to provide a thermodynamic basis and guidance for the crystallization process. Moreover, to fully analyze the LLPS nucleation mechanism of beta-alanine, the tie lines of the ternary diagram were constructed, and the site of nucleation was determined. Besides, on the basis of the phase diagram, evaporative crystallization was performed to investigate offing-out crystallization. Furthermore, tabular crystals, octahedron shaped crystals, and spherical crystals were obtained respectively from normal crystallization, offing-out crystallization, and quasi emulsion solvent diffusion crystallization.