A new look atφ-pH diagram (Ⅰ)
———All-equilibriumφ-pH diagram for M-H2O system①
———All-equilibriumφ-pH diagram for M-H2O system①
(Department of Metallurgy Science and Engineering, Central South University,
Changsha 410083, P.R.China)
Changsha 410083, P.R.China)
Abstract: A new viewpoint of computer program poubaix diagram was proposed on traditionalφ-pH diagrams. All equilibrium principle and activity term method were used to plotφ-pH diagrams for M-H2O systems based on the thermochemical database developed. And a new method———arithmetic-geometric method is used to solve nonlinear equations group. The calculation procedure is proved to be efficient and convergent. The method seldom depends on artificial intervention and can extend to multi-component all equilibriumφ-pH diagrams such as M-ligand- H2O system.
Key words: Pourbaix diagram; activity term method; all-equilibrium; nonlinear equation group; Pb- H2O system