植酸钠分解白钨矿的热力学分析  

Thermodynamic analysis of scheelite decomposition by sodium phytate

作　　者：刘旭恒 朱心蕊 陈星宇 李江涛 何利华 孙丰龙 赵中伟 LIU Xu-heng;ZHU Xin-rui;CHEN Xing-yu;LI Jiang-tao;HE Li-hua;SUN Feng-long;ZHAO Zhong-wei(School of Metallurgy and Environment,Central South University,Changsha 410083,China)

机构地区：[1]中南大学冶金与环境学院,长沙410083

出　　处：《中国有色金属学报》2022年第2期529-535,共7页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51774334)。

摘　　要：针对植酸盐分解白钨矿的问题,绘制了298 K温度下Ca-Phy-W-H_(2)O体系的热力学平衡图,阐明了体系中各物质的优势区域、重要组分随pH值和游离植酸总浓度的变化规律,进一步研究植酸盐分解白钨矿的可行性及热力学条件。理论分析表明,植酸盐可有效分解白钨矿,随着pH值的升高,稳定生成的固相产物依次为H_(2)WO_(4)、CaWO_(4)和Ca_(6)Phy。当体系pH>7.5后,Ca^(2+)与Phy^(12−)的结合作用急剧增强,导致游离浓度迅速上升,在pH>10之后趋于平缓,此时固相分解产物为Ca_(6)Phy。溶液中维持较低浓度的游离植酸即可实现白钨矿的分解,同时提高溶液的pH可促进白钨矿的分解。In order to solve the problem of scheelite decomposition by phytate,the thermodynamic equilibrium diagram of Ca-phy-W-H_(2)O system at 298 K was drawn.The variation law of dominant regions and important components in the system with pH and total concentration of free phytic acid was clarified.The feasibility and thermodynamic conditions of phytate decomposition scheelite were further studied.Theoretical analysis shows that phytate can effectively decompose scheelite.With the increase of pH value,the stable solid products are H_(2)WO_(4),CaWO_(4) and Ca_(6)Phy.When pH>7.5,the binding of Ca^(2+)and Phy^(12−) increases rapidly,resulting in a rapid increase in the concentration of free and insignificant increase after pH>10.At this time,the solid phase decomposition product is Ca_(6)phy.The decomposition of scheelite can be achieved by maintaining a low concentration of free phytic acid in the solution,and increasing the pH value of the solution can promote the decomposition of scheelite.

关 键 词：Ca-Phy-W-H_(2)O体系 白钨矿 植酸盐 热力学 分解 

分 类 号：TF841.1[冶金工程—有色金属冶金]