Dataset for the study of kinetic and passivation limitations in titanium extraction via molten oxide electrolysis

The data were collected from electrochemical experiments conducted in a CaF₂-CaO-TiO₂ melt at 1740 K, aiming to elucidate the fundamental mechanisms responsible for the failure of direct titanium metal deposition.The dataset comprises:Electrochemical measurement data: Raw and processed data from cyclic voltammetry (CV), square wave voltammetry (SWV), and galvanostatic electrolysis (GE) using tungsten (W) and iron (Fe) electrodes under various conditions, revealing the multi-step reduction process of Ti⁴⁺.Material characterization data: Backscattered electron (BSE) images, elemental mapping, point analysis, and line scan profiles of cathode deposits and interfacial products obtained via scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and electron probe microanalysis (EPMA); X-ray diffraction (XRD) patterns for phase identification of post-electrolysis melt and deposits.High-temperature in-situ observation data: A sequence of in-situ images recorded by laser scanning confocal microscopy (LSCM) capturing the dissolution process of a titanium particle in the molten slag, along with particle size vs. time data extracted from image analysis, used to calculate the dissolution kinetic rate constant of titanium.This dataset systematically reveals the two fundamental limitations to titanium electrodeposition in the CaF₂-CaO-TiO₂ melt: the rapid formation of a CaTiO₃ passivation layer and the kinetic balance between titanium deposition and dissolution/re-oxidation.

The data are of significant value for understanding the bottlenecks of molten oxide electrolysis (MOE) technology and optimizing titanium extraction processes.