Near-Field Ptychographic Tomography of Liquid-to-Crystal Transformation in Cerium Oxalate Precipitation

This proposal aims to study the conversion of amorphous precursors to crystalline phases that occurs during the precipitation of rare earth minerals. Previously, we evidenced the formation of transient liquid and amorphous solid phases during the crystallization of cerium oxalate (CeOx) using far-field ptychographic X-ray computed tomography. However, these analyses have failed to give us information about the exact location and mechanism of the liquid- and/or amorphous-to-crystalline phase transformation. Here, we wish to exploit the ability of near-field ptychography at ID16A to scan larger samples and investigate later reaction stages where large crystals are formed. Combined with our previous work on the kinetics of the transient phases, this information will enable us to develop a new theory of non-classical crystallization so that we can better model and predict precipitation processes crucial to rare earth metal recycling in the nuclear, battery, and electronics industries.