利用Fe-P-N-H2O体系E-pH图对硝磷酸体系合成磷酸铁的热力学分析研究
E-pH diagram of Fe-P-N-H2O system for thermodynamic analysis on synthesis of ferric phosphate by nitro-phosphoric acid system
谷任权 1吴俊虎 1杨秀山 1张志业 1许德华 1钟本和1
作者信息
- 1. 四川大学化学工程学院,四川 成都 610065;教育部磷资源综合利用与清洁加工工程研究中心,四川 成都 610065
- 折叠
摘要
硝磷酸法合成磷酸铁新工艺因生产流程简单、磷源成本低、设备投资小、能耗较低、绿色环保而具有很强的竞争力.利用FactSage和HSC等热力学软件中已有的热力学数据并运用E-pH图的绘制原理,得到Fe-P-N-H2O体系不同浓度、298-473 K的E-pH关系图.研究表明,在水溶液中,磷酸铁具有较大的热力学稳定区域,能够很好地解释现有的液相沉淀法制备磷酸铁的实际操作条件.此外,从E-pH图中获得了共沉淀法合成磷酸铁的合适条件:温度为363 K左右、高氧化还原电位为0.5 V、适宜pH为1～3、浓度为0.01 mol/L,该工艺为硝磷酸体系共沉淀法合成磷酸铁提供了热力学理论依据.
Abstract
The new process for synthesizing ferric phosphate via the nitro-phosphoric acid method presents strong competitiveness due to its simple production process,low cost of phosphorus sources,small equipment investment,lower energy consumption,and environmentally friendly characteristics.E-pH relationship diagram is established for Fe-P-N-H2O system at various concentrations in 298-473 K through utilizing thermodynamic data available in software such as FactSage and HSC,and applying the constructing principles of E-pH diagrams.Research indicates that ferric phosphate has a large thermodynamically stable region in aqueous solution,which explains well the practical conditions of the existing liquid phase precipitation method for preparing ferric phosphate.Furthermore,suitable conditions for the co-precipitation synthesis of ferric phosphate obtained from E-pH relationship diagram are as follows:a temperature around 363 K,a high oxidation-reduction potential of 0.5 V,an optimal pH of 1 to 3,and a concentration of 0.01 mol·L-1.This process provides a thermodynamic theoretical basis for the synthesis of ferric phosphate by co-precipitation in the nitro-phosphoric acid system.
关键词
Fe-P-N-H20体系/磷酸铁/热力学Key words
Fe-P-N-H2O system/ferric phosphate/thermodynamics引用本文复制引用
出版年
2024
NETL
NSTL
万方数据