文献类型：期刊文献

英文题名：Study on the mechanism of vacuum carbothermal reduction of Ca3(PO4)2 enhanced by SiO2

作者：Long, Xianze Deng, Xue Lv, Xiaodong Wu, Qinghui Jin, Huixin Lu, Fanghai Yang, Jing Huang, Run

第一作者：Long, Xianze

通信作者：Huang, R[1]

机构：[1]Guizhou Univ, Sch Mat & Met, Guiyang 550025, Peoples R China;[2]Guizhou Prov Key Lab Met Engn & Energy Proc Saving, Guiyang 550025, Peoples R China;[3]Guizhou Inst Technol, Sch Mat & Energy Engn, Guiyang 550003, Guizhou, Peoples R China

第一机构：Guizhou Univ, Sch Mat & Met, Guiyang 550025, Peoples R China

通信机构：corresponding author), Guizhou Univ, Sch Mat & Met, Guiyang 550025, Peoples R China.

年份：2024

卷号：230

外文期刊名：VACUUM

收录：;EI(收录号：20244217191207);Scopus(收录号：2-s2.0-85206078389);WOS:【SCI-EXPANDED(收录号:WOS:001336440400001)】；

基金：The authors are especially grateful for financial support from the National Natural Science Foundation of China (Grant No. 52064010), the Metallurgical Solid Waste Resourcefulness, Efficient and Clean Utilization Innovation Team, Guizhou University, Guiyang, China (Grant No. [2024]01) , School projects and Education Commission projects, Guizhou University, Guiyang, China (Grant No. 703141233301) , the Key Nurturing Projects of Guizhou University (Grant No. [2019]07), and the Natural Science Research Project of Guizhou Provincial Department of Education ( [2022]041).

语种：英文

外文关键词：Ca3(PO4)2; Thermodynamics; Vacuum carbothermal reduction; SiO2; Reaction mechanism

摘要：Vacuum carbothermal reduction mechanism of Ca3(PO4)2 with addition SiO2 was studied by combining FactSage 8.1 thermodynamic theoretical calculations with experiments. The theoretical calculations showed that adding SiO2 effectively reduced the initial reaction temperature. The experimental results showed that the addition of SiO2 significantly improved weight loss and volatilization rates of phosphorus. Ca2SiO4 and CaSiO3 were generated during the reaction. When the SiO2/CaO ratio was 1.25 at 1300 degrees C, the reduction effect of Ca3(PO4)2 and the volatilization rate of phosphorus was optimal, with a volatilization rate of 91.98 %. Excessive SiO2 led to insufficient contact between the reactants and reducing agent C, thereby hindering the reaction. Simultaneously, a large amount of liquid phase was produced, which deteriorated the kinetic conditions of gas diffusion and affected the reaction. In the reduction process, Ca3(PO4)2 reacted with reducing agent C to generate CaO, then reacted with external SiO2 to generate low melting point CaSiO3, which wrapped the unreacted core. With an increase in the low melting point CaSiO3, the mass transfer in the reaction changed from diffusion mass transfer to flow mass transfer, which promoted the inward diffusion of reducing agent C to contact the unreacted core until the reduction reaction was completed.