A Change in the Specific Conductance of Solutions of High-Vanadium Heteropoly Acids in Redox Processes

Resumo

Changes in the values of specific conductance χ of the solutions of high-vanadium Mо−V−Р heteropoly acids (HPA-х) in redox processes are determined for the first time for the HPA-7 solution of the overall composition Н₁₀Р₃Мо₁₈V₇O₈₄, which is a highly efficient catalyst for oxidation processes. The dependences of χ on [HPA-7] at different temperatures and degrees of reduction m and the dependence of χ on m, are found. The relationship between χ and the equilibrium composition of the HPA-7 solution is shown. It was confirmed that the regenerated HPA-7 solutions completely restore their conductance and other physicochemical properties (redox potential E, density, viscosity, and pH), thereby proving the high stability as homogeneous catalysts of oxidative processes.