Справочник диаграмм состояния потенциал-рН (Диаграммы Пурбе).
National Institute of Advanced Industrial Science and Technology Research Center for Deep Geological Environments.
Naoto TAKENO. May 2005. — 285 p.This open file report aims to present an intercomparison of thermodynamic databases by means of EhpH diagrams, which are practical and useful for understanding geochemical behavior of elements. An Eh-pH diagram depicts the dominant aqueous species and stable solid phases on a plane defined by the Eh and pH axes. In an Eh-pH diagram, the solid stability area is related to the saturation condition, and dominant aqueous species give us fundamental information on sorption and colloid phenomena as well as surface characteristics of materials. Eh-pH diagrams are thus essential to understanding solute and radionuclide transport in groundwater.
The most well-known studies on comprehensive Eh-pH diagrams are those of Pourbaix (1966) and Brookins (1988). The former discussed corrosion, passivation and immunity of materials, while the latter reported geochemical aspects of the geological disposal of radioactive wastes. These studies have been followed by many thermodynamic databases. With the ever increasing CPU power of computers, we have started utilizing geochemical codes for calculation of complex chemical reactions. Thus, thermodynamic databases have gained importance
from a practical perspective.
Certain geochemical codes enable us to obtain Eh-pH diagrams easily and quickly. With the aid of software, Eh-pH diagrams can provide us with good insight into the state of the art in thermodynamic databases and the differences between them.
It should be noted that this open file report presents the Eh-pH diagrams calculated from databases ”as is”, without any critical comments. It should also be noted that Eh-pH diagrams represent one aspect of thermodynamic databases and databases are often updated, thus this report is only a snapshot of the present. I would be very pleased if this open file report proves useful in helping the readers use thermodynamic databases.Справочник содержит 139 диаграмм состояния Е (В) - рН системы Ме-О-Н, где Ме-металл. Диаграммы наглядно отображают термодинамически устойчивые формы существования элементов (ионов, молекул, атомных кристаллов и металлов) в растворах при различных значениях водородного показателя pH и окислительно-восстановительного потенциала E. Из них можно определить условия большинства кислотно-основных и окислительно-восстановительных реакций соединений данного элемента без учета взаимодействия с посторонними ионами, а сопоставляя диаграммы Пурбе для двух элементов можно предсказать окислительно-восстановительные реакции между их соединениями.
Справочник может быть полезен для исследователей в области электрохимии и физической химии, аспирантов и студентов химико-технологических вузов.
