Electro-deoxidation of V_2O_3 in molten CaCl_2-NaCl-CaO

摘要

The electro-deoxidation of V_2O_3 precursors was studied. Experiments were carried out with a two-terminal electrochemical cell, which was comprised of a molten electrolyte of CaCl_2 and NaCl with additions of CaO, a cathode of compact V_2O_3, and a graphite anode under the potential of 3.0 V at 1173 K. The phase constitution and composition as well as the morphology of the samples were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). 3 g of V_2O_3 could be converted to vanadium metal powder within the processing time of 8 h. The kinetic pathway was investigated by analyzing the product phase in samples prepared at different reduction stages. CaO added in the reduction path of V_2O_3 formed the intermediate product CaV_2O_4.