V-H2O体系的溶解组分优势区域图和电势-pH 图

运用浓度比较法, 对25 ℃时V-H2O体系进行热力学分析和电化学分析, 编程计算出各溶解组分浓度, 以及固相和液相、各固相间边界线, 确定固相区和液相区的位置. 在此基础上, 绘制出了总V浓度cT(V)=1.0×10-5 mol·L-1时V-H2O体系的溶解组分优势区域图和电势-pH图以及cT(V)=1.0×10-7 mol·L-1时V-H2O体系的电势-pH图. 电势-pH图结果表明在一定温度和压力下, 各相稳定区取决于体系中溶液态物质的总浓度. 随cT(V)的减小, 溶液稳定区增大, 各固相稳定区均不同程度减小.

Predominance Diagrams of Dissolved Species and Potential-pH Diagrams of V-H2O System

The predominance diagram of dissolved species and potential -pH diagrams of V-H2O system were studied at 25 ℃ by concentration comparison method. The concentration of dissolved species, the borderlines for liquid phases or solid phases, and the borderlines between solid and liquid phase were calculated using the computer programming on the basis of thermodynamic analysis and electrochemistry analysis. The solid regions and liquid regions of kinds of species were ascertained. The predominance diagram of dissolved species and two potential-pH diagrams (at total concentration of V: cT(V)=1.0×10-5 and cT(V)=1.0×10-7 mol·L-1, respectively) of the V-H2O system were plotted. The results showed that under a certain temperature and pressure, the phase stable regions were determined by the total concentration of the species. The stable region of solution was enlarged along with the decreasing of cT(V), whereas the regions of solid phases were reduced.