钼酸钙浸出体系lgc?pH图的构建及其浸出行为分析
Understanding the leaching behavior of calcium molybdate through the construction of lgc−pH diagrams
张文娟 1车键勇 1朱纪念 2陈国举 2夏柳 1陈军 1王成彦1
作者信息
- 1. State Key Laboratory of Advanced Metallurgy(University of Science and Technology Beijing),Beijing 100083,China;School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China
- 2. State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization,Jinchang 737100,China
- 折叠
摘要
CaMoO4是钼钨钙矿的主要成分,也是钼冶金过程中重要的中间产物.目前,钼酸钙的浸出主要集中于工业实践及实验研究,而浸出过程的热力学分析较少且不够系统.本文通过绘制Ca-Mo-H2O,Ca-Mo-PO4-H2O,Ca-Mo-SiO4-H2O,Ca-Mo-CO3-H2O,Ca-Mo-Y(EDTA)-H2O和Ca-Mo-F-H2O体系的lgc−pH图,研究了钼酸钙在常用浸出体系(Na2EDTA,Na2SiO3,Na3PO4,Na2CO3和NaF)中的分解行为.结果表明,CaMoO4及生成固体产物的稳定区依赖于pH值和浸出剂的浓度,适当的增加pH值和浸出剂浓度能够增加CaMoO4的溶解,促进浸出反应的进行.基于热力学分析,研究了CaMoO4在不同体系中的浸出行为,其结果与热力学分析完全吻合.本文构建的热力学图能够用于解释钼湿法冶金过程遇到的相关问题,并能够为CaMoO4的处理提供热力学途径.
Abstract
CaMoO4 is not only the main component of powellite, but also a key intermediate product in molybdenum metallurgy. The current leaching of CaMoO4 is mainly in experimental and industrial research, and seldom in theoretical analysis. In this research, lgc−pH diagrams for Ca-Mo-H2O, Ca-Mo-PO4-H2O, Ca-Mo-SiO4-H2O, Ca-Mo-CO3-H2O, Ca-Mo-Y(EDTA)-H2O, and Ca-Mo-F-H2O systems were constructed to predict the dissolution behavior of CaMoO4 in Na2EDTA, Na2SiO3, Na3PO4, Na2CO3, and NaF solutions. The diagrams suggest that CaMoO4 can be dissolved by the five types of solutions and the solid products, for example, Ca5(PO4)3OH, CaSiO3, Ca3Si2O7, CaCO3 and CaF2 were generated depending on the added reagent, while calcium combines with EDTA to form soluble CaY2− in Na2EDTA solution. The stability regions of CaMoO4 and solid products are dependent on the ion concentration and pH value. Meanwhile, the proper increase of reagent concentration and pH is beneficial for raising the solubility of molybdenum. The leaching experiments of synthetic CaMoO4 in various media indicate that CaMoO4 can be dissolved with a high leaching efficiency which was in accord with the thermodynamic analysis. This work presents the construction of thermodynamic diagrams that is useful in the analysis of the encountered phenomena in molybdenum hydrometallurgy and provides a thermodynamic approach for treating CaMoO4.
关键词
热力学/钼酸钙/浸出/lgc−pH图Key words
thermodynamic/CaMoO4/leaching/lgc−pH diagrams引用本文复制引用
基金项目
State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization,China(JKY2019-10)
National Natural Science Foundation of China(51804029)
出版年
2023
NETL
NSTL
维普
万方数据