Study on gasification dephosphorization of phosphorus magnetite reduced by SiC

Abstract

AbstractThe mechanism of reduction and dephosphorization of phosphorus-containing magnetite was studied using SiC as reducing agent. The thermodynamic conditions for the reduction of Ca3(PO4)2 and Fe3O4 by SiC were simulated by FactSage7.1 thermodynamics software, respectively, indicating that the reduction of Ca3(PO4)2 by SiC is thermodynamically feasible, but the kinetic conditions of the system are not good when no liquid phase is formed. The Fe2SiO4 liquid phase can be formed by reducing Fe3O4 by SiC at 1200 ℃. When the SiC ratio is 10 wt.%, the liquid phase content is the largest, which can reach more than 60 wt.%. Therefore, in this paper, the Fe2SiO4 liquid phase generated by the reduction of Fe3O4 by SiC is used to improve the kinetic conditions of the reduction of Ca3(PO4)2 by SiC at high temperature, and relevant experiments were carried out. The research results show that the system generates a suitable amount of liquid phase at 1250 °C, and the gasification dephosphorization rate is the highest, which is 39.89 wt.%, at 1200 °C, the reduction reaction was not fully carried out, and the dephosphorization rate by gasification was only 23.79 wt.%. At 1300 °C, Fe3O4 was completely reduced to metallic Fe, which combined with the reduced P4 gas to form Fe2P. Gasification dephosphorization rate is only 28.25 wt.%.