硅热法提磷热力学分析与试验  

Thermodynamic Analysis and Testing of Phosphorus Extraction by Silicothermic Process

作　　者：程晓宇 庞建明 李石稳 赵志民 刘飞 CHENG Xiaoyu;PANG Jianming;LI Shiwen;ZHAO Zhimin;LIU Fei(Central Iron and Steel Research Institute,Beijing 100081,China;Resource Application and Alloy Materials Division,China Iron and Research Institute Group,Beijing 100081,China)

机构地区：[1]钢铁研究总院,北京100081 [2]中国钢研科技集团有限公司资源应用与合金材料事业部,北京100081

出　　处：《矿冶工程》2023年第6期112-115,共4页Mining and Metallurgical Engineering

基　　金：承德国家可持续发展议程创新示范区建设科技专项(202206F005)。

摘　　要：采用硅热法提取黄磷,通过热力学计算,明晰了硅热法提磷的主要化学反应以及反应吉布斯自由能,并通过实际试验验证了工艺流程的可行性。结果表明,硅热法提磷主反应为:2(3CaO·P_(2)O_(5))+5Si+SiO_(2)=2P_(2)(g)+6CaO·SiO_(2);真空度对反应起正向作用,反应体系压强越低,反应吉布斯自由能越小,硅热还原反应越容易发生;提高温度可促使反应正向进行,相同温度下适当延长还原时间,可提高反应还原率;常压下1250℃反应2.5 h,硅热法提磷可得到纯度95.03%的粗磷(黄麟),干渣残磷量为1.45%。硅热法制备黄磷过程中采用硅质还原剂,避免了焦炭的使用,符合低碳发展战略。A silicothermic process was adopted to extract phosphorus,and the main chemical reactions and Gibbs free energy were clarified by thermodynamic calculation.The feasibility of the process was then verified by performing practical experiments.The main reaction of silicothermic process for phosphorus extraction is as follows:2(3CaO·P_(2)O_(5))+5Si+SiO_(2)=2P_(2)(g)+6CaO·SiO_(2).The vacuum degree can promote the reaction to proceed in the forward direction,and a reaction system with lower pressure can lead to smaller standard Gibbs free energy of the reaction,leading to silicothermic reduction reaction occuring much easier.Increasing temperature can promote the reaction to proceed in the forward direction,and prolonging reduction time properly at the same temperature can improve the reduction rate of the reaction.After a reaction at 1250℃for 2.5 h under normal pressure,rough phosphorus(yellow phosphorus)with purity of 95.03%can be obtained by adopting silicothermic process,and the content of residual phosphorus in the dry slag is 1.45%.It is shown that using siliceous reductant in the silicothermic process for preparing yellow phosphorus can avoid the usage of coke,which conforms to low⁃carbon development strategy.

关 键 词：磷化工 黄磷 硅热法 热力学计算 还原率 工业硅 

分 类 号：TQ126.3[化学工程—无机化工]