A new method of computing multi-component E-pH diagrams

Abstract

Aqueous E-pH Diagram is an essential tool for analyzing hydrometallurgical and corrosion processes. Due to the requirements for environmental protection and energy saving in recent years, waste water processing and hydrometallurgical process of concentrate have been greatly developed. The construction of E-pH diagrams has turned to multi-component systems. However, there are some limits in plotting such diagrams. There is only one diagram for one multi-component system, which can not reflect the truth of the aqueous reaction. In the paper, a new computation method is proposed to construct E-pH diagrams. Component activity term is used to determine the boundary of stable areas. For the multi-component systems, different atom ratios of elements have been taken into account. M-S-H₂O system is chosen to study since it is of importance in metallurgical solution. Compared with conventional methods, the algorithm is simple and conforms to real conditions.

Keywords

computation algorithm of E-pH diagrams / component activity term / M-H₂O system / M-S-H₂O system / atom ratios

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