HSCChemistry使用基础手册EhpHDiagram模块中文.docx

17. Eh - pH - DIAGRAMS (Pourbaix-diagrams)
Eh-pH-diagrams show the thermodynamic stability areas of different species in an aqueous solution. Stability areas are presented as a function of pH and electrochemical potential scales. Usually the upper and lower stability limits of water are also shown in the diagrams with dotted lines. Traditionally these diagrams have been taken from different handbooks12. However, in most handbooks these diagrams are available only for a limited number of temperatures, concentrations and element combinations.
Eh-pH图显示不一样物种在水溶液中热力学稳定区。稳定地域作为一个潜在尺度和电化学作用pH值。通常上、水下稳定极限也和虚线图所表示。传统上，这些图已从不一样handbooks12。然而，在大多数手册这些图是只有数量有限温度，浓度和元素组合。
The Eh-pH module of HSC Chemistry allows the construction of diagrams in a highly flexible and fast way, because the user can draw the diagrams exactly at the selected temperature and concentration.
HSC化学Eh-pH模块许可在一个高度灵活和快速方法图解，因为用户能够画出图形，在选定温度和浓度。
The Eh-pH-module is based on STABCAL - Stability Calculations for Aqueous Systems - developed by H.H. Haung, at Montana Tech., USA9,10.
Eh-pH模块是基于stabcal稳定性计算水系统由H.H.黄发达，蒙大纳科技，usa9,10。
17.1 Introduction
Eh-pH-diagrams are also known as Pourbaix Diagrams according to author of the famous Pourbaix diagram handbook12. The most simple type of these diagrams is based on a chemical system consisting of one element and water solution, for example, the Mn-H2O-system. The system can contain several types of species, such as dissolved ions, condensed oxides, hydroxides, oxides, etc. The Eh-pH-diagram shows the stability areas of these species in the redox potential-pH-coordinates.
Eh-pH图也称作Pourbaix图依据著名Pourbaix图handbook12作者。这些图最简单类型是基于化学系统组成一个元素和水处理方案，比如，在mn-h2o-system。该系统能够包含多个类型物种，如溶解离子，浓缩氧化物，氢氧化物，氧化物，等电位-pH图显示在氧化还原电位pH这些物种稳定区域坐标。
Usually the redox potential axis is based on the Standart Hydrogen Electrode (SHE) scale designated Eh, but other scales can also be used. The redox potential of the system represents its ability to change electrons. The system tends to remove electrons from the species when the potential is high (Eh > 0). These conditions may exist near the anode in the electrochemical cell, but can also be generated with some oxidizing agents (Cu + H2O2 = CuO + H2O). In reducing conditions, when potential is low (Eh < 0), the system is able to supply electrons to the species, for example, with a cathode electrode or with some reducing agents.
通常氧化还原电位轴是基于标准氢电极（她）规模划啊，但也能够使用其它表。该系统氧化还原电位代表其改变电子能力。系统会删除电子从物种可能是当高（EH > 0）。这些条件可能存在在电化学电池阳极，但也能够和部分氧化剂（H2O2生成Cu +铜+ H2O =）。在还原条件下，当为低电位（Eh＜0），该系统能够提供电子物种，比如，和阴极电极或和还原剂。
The pH of the system describes its ability to supply protons (H(+a)) to the species. In acid conditions (pH < 7) the concentration of the protons is high and in caustic conditions (pH > 7) the concentration of protons is low.
pH值系统描述其提供质子能力（H（+））种类。在酸性条件下（pH＜7）质子浓度较高，在碱性条件下（pH＞7）质子浓度低。
Usually a large amount of different species exist simultaneously in the aqueous mixtures in fixed Eh-pH-conditions. The Pourbaix diagrams simplify this situation a lot by showing only the predominant species which content is highest in each stability areas. The lines in the diagrams represent the Eh-pH-conditions where the content of the adjacent species is the same in the equilibrium state. However, these species always exist in small amounts on both sides of these lines and may have an effect on practical applications.
通常一个大不一样物种数量同时存在固定Eh-pH条件水混合物。Pourbaix图简化这种情况很多只显示优势种，内容是每个稳定性最高地域。图中线代表Eh-pH条件下相邻物种内容是在平衡状态下相同。然而，这些品种全部存在少许这些线两侧，可能对实际应用影响。
The lines in the diagrams can also be represented with chemical reaction equations. These reactions may be divided into three groups according to reaction types:
图中线也能够用化学反应方程式。这些反应可分为三组，依据反应类型：
1. Horizontal lines. These lines represent reactions that are involved with electrons, but are independent of pH. Neither H(+a)-ions nor OH(-a)-ions participate to these reactions.
1水平线。这些线代表反应，包含电子，但独立博士没有H（+）离子和OH（-）-离子参与反应。
2. Diagonal lines with either positive or negative slope. These lines represent reactions that are involved with both electrons and H(+a)-and OH(-a)-ions.
2。对角线或正或负斜率。这些线代表反应，包含电子和H（+）和（-）-离子哦。
3. Vertical lines. These lines represent reactions that are involved either with H(+a)- or OH(-a)-ions, but are independent of Eh. In other words, electrons do not participate with these reactions.
3垂直线。这些线代表反应，可能和H（+）或（-）-离子哦，但独立啊。换句话说，电子不参与这些反应。
The chemical stability area of the water is shown in the Eh-pH-diagrams with dotted lines. The upper stability limit of water is based on the potential when the oxygen generation starts on the anode. It is specified by the reaction:
水化学稳定性区域是在虚线Eh-pH图所表示。水上稳定极限是基于势当氧代开始在阳极。它是由指定反应：
2 H2O = O2(g) + 4 H(+a) + 4 e-
2 H2O = O2（g）+ 4 H（+）+ 4—
The lower stability limit is based on hydrogen formation on the cathode. It is specified by the reaction:
较低稳定极限是基于阴极上氢形成。它是由指定反应：
2 H(+a) + 2 e- = H2(g)
2 H（+）+ 2 E = H2（g）
The construction of the diagrams with HSC Chemistry EpH module is quite a simple task. However, several aspects must be taken into account when specifying the chemical system and analyzing the calculation results, for example:
用HSC-Chemistry弗模块图建设是一个相当简单任务。然而，多个方面必需考虑指定化学系统分析计算结果，比如：
1. A basic knowledge of chemistry, aqueous systems and electrochemistry or hydrometallurgy is always needed in order to draw the correct conclusions.
1。一个基础化学知识，水系统和电化学或湿法总是为了得出正确结论。
2. The EpH module carries out the calculations using pure stoichiometric substances. In practice minerals may contain impurity elements and the composition may deviate slightly from the stoichiometric one.
2。弗模块进行计算，采取纯化学物质。在实践中可能含有杂质元素和矿物组成可能稍微偏离化学计量。
3. There are always some errors in the basic thermochemical data of the species. This may have significant effect on the results, especially if the chemical driving force of the reaction is small. Usually small differences between Pourbaix diagrams from different sources can be explained by the slightly different basic data used.
3。总有部分物种基础热化学数据部分错误。这可能会对结果有显著影响，尤其是假如该反应化学驱动力小。通常小差异Pourbaix图从不一样起源能够经过使用略有不一样基础数据解释。
4. Sometimes data for all existing species is not available from the HSC database or from the other sources. This will distort the results if the missing species are stable in given conditions. The missing unstable species will have no effect on the results.
4。有时数据中全部现存物种是无法从数据库或从其它起源造血干细胞。这会扭曲结果假如丢失物种是在特定条件下稳定。失踪不稳定物种会对结果没有影响。
5. The EpH module does not take into account the non-ideal behavior of aqueous solutions. However, in many cases these ideal diagrams give a quite good idea of the possible reactions in aqueous solutions, especially if the driving force of the reactions is high.
5。弗模块没有考虑到溶液非理想行为。然而，在很多情况下，这些理想图给出可能反应一个相当好主意在水溶液中，尤其是假如该反应驱动力是高。
6. Thermochemical calculations do not take into account the speed of the reactions (kinetics). For example, the formation of the SO4(-2a) ion may be a slow reaction. In these cases metastable diagrams created by removing such species from the system may give more consistent results with the experimental laboratory results.
6。热化学计算不考虑反应速度（动力学）。比如，在形成SO4（2A）离子可能是一个缓慢反应。在这些情况下，亚稳态图，从系统中除去这些物种发明了能够提供更一致结果和试验结果。
The HSC user must be very careful when drawing conclusions from Eh-pH-diagrams due to these limitations and assumptions. However, these diagrams may offer extremely valuable information when combining the results with the experimental work and with a good knowledge of aqueous chemistry. There is no universal kinetic or thermochemical theory available, which could entirely substitute traditional experimental laboratory work with pure theoretical calculation models.
HSC用户必需很小心，当得出结论Eh-pH图因为这些限制和假设。然而，这些图能够提供极有价值信息时，将结果和试验工作和和水化学知识好。有没有通用动力学、热化学理论可用，可完全替换传统纯理论计算模型试验试验室工作。
More information on Eh-pH-diagrams, calculation methods and applications can be found from different handbooks, for example, from the Pourbaix Atlas12.
在Eh-pH图计算方法和应用更多信息，能够发觉不一样手册，比如，从儿atlas12。17.2 Chemical System Specifications

Fig. 1. Selecting elements and species for the Eh - pH - diagram.

The EpH Diagram selection in the HSC main menu will show the EpH-form, Fig. 1. The user must specify the chemical system, which will be used to calculate the diagram in this form. Assume that system contains Cu, S and H2O. The following steps should be specified in order to create the diagram:
在主菜单中选择HSC弗图将显示弗形，图1。用户必需指定化学系统，这将被用来计算这种形式图。假设系统含有Cu，S和H2O。以下步骤应该被指定为创建图表：
1. Select Main Element: Select one element from the list. This element will be used as the “main” element in the first diagram, i.e. all species, which are shown in the diagram, will contain this element. The user can easily change the main element selection later on in the diagram form. The Cu has been selected in this example.
1。选择关键原因：从列表中选择一个元素。本单元将作为第一个图“关键”元素，即全部物种，这是图中所表示，将包含此元素。用户能够很轻易地改变关键元素选择，以后在图形式。铜已在本例中选择。
2. Select Other Elements: Select other elements to the system. Up to 7 elements can be selected but it is recommended to use less, because large amount of elements and species increase calculation time and could cause some other problems. S has been selected in this example. Note: It is not necessary to select H and O, because these are always automatically included.
2。选择其它元素：选择其它元素系统。高达7元素能够选择但提议少用，因为元素和物种大量增加计算时间和可能引发其它问题。已经在本例中选择。注：这是没有必需选择H和O，因为这些全部是自动地包含。
3. Search Mode: This selection specifies the type of species, which will be collected from the database. It is recommended to use default selections. Note: Condensed = solid substances, Aqueous Neutrals =dissolved species without charge, Aqueous Ions = dissolved ions, Gases = gaseous species without charge, Gas Ions = gaseous ions, and Liquids = liquid species.
3。搜索模式：选择指定物种类型，它将被从数据库中搜集。提议使用默认选择。注：凝结为固体物质，水中立=溶解不收费，水离子=溶解离子，气体=气态物种没有电荷，气体离子=气态离子，和液体=液体种类。
4. OK: Press OK to start the search from the database.
4。好：按OK从数据库开始搜索。
5. Select Species: Usually you can select all species to the diagram by pressing All. In some cases, however, it is useful to remove unnecessary species from the system. This will decrease calculation time and simplify diagrams. Note: A) By pressing simultaneously Ctrl-key and clicking with the mouse it is easy to make any kind of selection. B) By double clicking the species it is possible to see more information of the species. Load CUS25.IEP file to see the selected species of this example.
5。树种选择：通常您能够选择全部物种图按全部。然而，在一些情况下，它是从系统中删除无须要物种有用。这将降低计算时间和简化图。注：a）按下Ctrl键，同时用鼠标很轻易做出什么样选择点击。B）双击物种有可能看到更多物种信息。负载cus25.iep文件看这个例子选择种类。
6. Temperature: The user must specify at least one temperature for the diagram. Up to four temperatures may be specified in order to draw combined diagrams, which show the effect of temperature. The temperatures 25, 50, 75 and 100 °C have been selected in this example, Figs. 1 and 2.
6。温度：用户必需指定最少一个温度图。高达四温度能够被指定为绘制组合图，显示温度影响。温度25，50，75和100°C已在本例中选择，无花果。1和2。
7. Criss-Cobble: This option enables HSC to extrapolate the heat capacity function of the aqueous species if this data is not given in the database11, see Chapter 28.4.
7。纵横交错卵石：此选项使HSC推断水种热容量功效假如这个数据是不是在database11给出，见28.4章。
8. EpH: Press EpH to start the File Save dialog and Calculation of the diagram. You can also press File Save in order to save the data for later use without running the calculation procedure.
8。弗：按弗开始保留文件对话框图和计算。你也能够按文件保留为数据保留供以后使用无需运行计算程序。
9. Diagram: Pressing the EpH button will show the Diagram specification form, see Chapter 17.3 and Fig 2. By pressing Diagram in Fig. 2 you will see the default diagram.
9。图：按弗按钮将显示图规范形式，见17.3章图2。按图在图2中你会看到默认图。
17.3 Eh - pH - Diagram Menu

Fig. 2. Default values for the Eh - pH - diagram.

The EpH-diagram menu shows a summary of the chemical system specifications as well as selected default values for the diagram. The fastest way to go forward is to accept all the default values and press Diagram for simple EpH diagrams or Combine for combined diagrams. Usually at the begining, there is no need for modifications to the default values. However, it is important to understand the meaning of these settings because they may have strong effect on the diagram. The details of the diagram menu options are explained in the following paragraphs.
Eph图菜单显示化学系统规范总结和选择默认值图表。走最快方法是接收全部默认值，并按图简单弗图或结合组合图。通常在开始时，没有必需为默认值修改。然而，它是了解这些设置意义关键，因为她们可能在图上强烈影响。图中菜单选项细节在下面解释。
1. File Open
1。打开文件
The EpH module can also be used as an independent application, in these cases the data for the diagram may be read from *.IEP files by pressing File Open. Normally the system specifications are automatically transferred from the system specification sheet to the diagram menu, Fig. 2.
Eph模块也能够作为一个独立应用程序，在这些情况下，图数据能够读自*。按IEP文件打开文件。通常系统规格说明书由系统自动转移到关系图”菜单，图2所表示。
The diagram specifications can be modified in the diagram menu. The selections can be saved for later use with File Save IEP selection from the menu. The IEP-files may also be edited by any text editor like Windows Notepad. Please be careful as any mistake may cause unpredictable results. The calculation results may be saved to *.EPH file with File Save EpH selection and loaded back with File Open EPH selection which causes the diagram to be automatically recalculated.
图规格能够在关系图”菜单修改。选择能够保留供以后使用保留文件时选择菜单。IEP文件能够使用任何文本编辑器如Windows记事本编辑。请小心，任何错误全部可能造成不可预知结果。计算结果能够保留到文件和文件保留。弗弗选择和装回文件打开弗选择使图自动重新计算。
2. Species and DG-data workbook
2。物种和DG数据手册
The selected species and calculated DG-data based on the enthalpy, entropy and heat capacity values of the HSC database is shown on the Species sheet of the diagram workbook, Fig. 2. The species are arranged according to elements and species type. The user can modify the DG-data as well as add or remove species in this sheet. The Species sheet makes it possible to use data and species which cannot be found in the HSC database, for example:
选择种类和计算DG数据基于焓，熵和热HSC数据库容量值在图表工作簿物种表所表示，图2。种类按要素和种类。用户能够同时添加或删除本片种DG数据修改。物种表能够使用数据和物种而不能在HSC数据库中找到，比如：
A. The published Pourbaix diagrams are often based on DG-data which is given in the original papers. This DG-data can be used in the Species sheet to replace the default values based on the HSC database if necessary. Note that these DG-values can also be calculated from the standard potential values using equation 1
A.发表Pourbaix图往往是基于DG数据是原始文件。这DG数据可用于物种片替换默认值基于HSC假如必需数据库。注意这些DG值也能够用公式1标准电位值计算
, [1]
，[ 1 ]
where n is the charge transferred in the cell reaction, F is the Faraday constant (23045 cal/(V*mol)) and E is the standard electrode potential in volts. Note: Give DG-data for the selected temperatures, usually these values are only available at 25 °C.
其中n是细胞反应电荷转移，F是法拉第常数（23045卡/（V *摩尔））和E是伏特标准电极电位。注：为选定温度给DG数据，通常这些值在25°C.只有
B. Sometimes all necessary species are not available in the HSC database. These missing species can be added to the chemical system specification if the user has the DG-values or chemical potential data for these species. The new species may be added by inserting empty row with Insert Row selection and typing formula and DG-values to this row.
B.有时必需物种没有造血干细胞库。这些失踪物种能够被用户假如有DG值或化学这些物种潜在数据添加到化学系统规范。新物种能够