Single Fe2B Phase Particle Production by Calciothermic Reduction in Molten Salt

Abstract

In this study, calciothermic single phase iron boride(Fe2B) production was investigated in a scalable molten salt system, starting from inexpensive, easily accessible oxide materials. First, the formation of Fe2B was examined in detail in the light of thermodynamic data and literature. After, effects of CaO amount (0-10 wt.%) and time (30-60 min) on particle synthesis were investigated under at constant 3.0 V cell voltage and 1273 K temperature. It was determined that the average current increased continuously with the increase in the amount of CaO, and the current efficiency increased up to 7% by weight of CaO. After the CaO ratio was determined, the effect of the electrolysis duration was examined. In durations experiments, it has been observed that, in 30 minutes’ duration, the particles are composed of Fe, Fe2B and FeB, and by increasing the experiment time to 60 min, single-phase Fe2B particles are obtained. The magnetic properties of the single-phase Fe2B particles obtained at the end of the experiment period of 60 minutes were investigated by VSM. The saturation magnetization, permanent magnetization and coercivity values of the Fe2B particles were determined as 90.718 emu/g, 33.311 Oe, 1.684 emu/g, respectively.

Keywords

• molten salt electrolysis
• iron boride
• calciothermic reduction
• borides

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