HSC CHEMISTRY - Chemical Reaction and Equilibrium Thermodynamics
Chemical Reaction and Equilibrium Software
HSC Chemistry offers a quick and easy way to solve chemical reaction problems on your personal computer. The HSC has a wide range of application possibilities in industry, research and education. All calculations utilize automatically integrated thermochemical database that includes more than 15000 compounds.
Traditionally, researchers have tested their ideas by writing out reaction equations, and then calculated equilibrium constants and heats of reactions from standard thermochemical data. A time-consuming search for this data with standard state conversions was needed, however.
HSC does all the above instantly - you simply type the reaction equation in the input field and HSC gives you the heat of the reactions, equilibrium constant at any temperature and amount of species. HSC even checks the elemental balance and gives potentials vs. the standard hydrogen electrode for electrochemical reactions.
The calculated heat of reaction is the amount of heat that will be absorbed or released in the reaction. The equilibrium constant predicts the direction of the reaction. User input may be in the form of simple formulas or chemical reactions:
Mg = Mg(g)
2Al + 3/2O2(g) = Al2O3
H2O = 1/2O2(g) + 2H(+a) + 2e-
Ag = Ag(+a) + e-
3NO2(-a) + H(+a) = 2NO(g) + H20 + NO3(-a)
2Al(+3a) + 3S(-2a) + 6H2O = 2Al(OH)3 + 3H2S(g)
Heat balance calculations are needed to estimate the energy requirements and the cost of the process, as well as the operation preconditions. In fact no process will work if the heat balance is not met.
Input and output species, as well as their amounts and temperatures, are needed for the calculations. HSC recalculates the heat balance every time the initial conditions are changed. In this way you can, for example, find the optimum preheating temperature for raw materials to offset electrical heating of reactor system.
Theoretical heat balances can be taking species and amounts from the reaction equations or equilibrium calculations. Real heat balances can be calculated by taking species and amounts from experimental results. These balances are very useful when scaling up processes from laboratory to industrial scale.
By pointing and pressing on the appropriate buttons, the user can select either Celsius or Kelvins for temperature, moles or kilograms for amounts and calories or joules for energy units.
The Temp Bal button is used to get product temperature at zero heat balance. In the case of gaseous combustion processes with zero heat exchange to the environment, this yields the adiabatic flame temperature.
Both input and results can be saved as text files by pressing the Save button. This assures the files will be available later for editing in HSC or use in other programs.
calculations offer a practical way to observe the effects of process variables, such as temperature and amounts of raw materials on product composition.
With this program option you can calculate equilibrium composition and amounts of prevailing phases in any reactor. You only specify the raw material amounts, temperatures and the species of the system. These species can be specified by selecting the elements of the system, or typing the formulas, or by editing the old file. Activity coefficients can be given, if necessary, as constants or as functions of temperature and composition.
Calculations can be repeated at stepwise intervals over the range of raw materials amounts or reaction temperatures in order to visualize the effect of these process variables. For example, you can observe the effect of temperature on arsenic evaporation from copper-iron sulfides, or the effect of chlorine feed on titanium chlorination.
Equilibrium compositions are calculated using the Gibbs energy minimization method as soon as the user saves the input data by pressing the Save button. The results can raw material amount, temperature, then be presented graphically as a function of partial pressure, etc.
You can select linear or logarithmic scale and set maximum and minimum values for the x- and y-axis.
The tabular numerical data which is used to draw the diagram can be saved as a normal text files by pressing the Table button. These files can be read, for example, in spreadsheet programs for further calculations.
A paper copy of the diagram can be obtained at the highest resolution of your Windows-supported printer by pressing the Print BW button. If you have a color printer press the Print Col button.
A special Cell Equilibrium
calculation option is also available for calculating charge and composition of phases in electrochemical cells, such as batteries.
The simplest calculation option is a versatile program for calculating formula weights. It accepts any form of chemical formula using conventional organic or inorganic expressions (without superscripts and subscripts).
Typical entries might be:
NaBO3*4H2O, H2(Sn(OH)6), (C2H5)2O, etc.
The program displays the formula weight and elemental composition as both weight and atomic percentages. A paper copy of results is immediately available by pressing the Print button.
Phase Stability Diagrams
Phase stability diagrams offer a quick way to locate the stability regions of different phases at varying partial pressures of oxygen, sulfur, chlorine, nitrogen oxide, etc. The diagrams are quickly constructed in the following steps:
- Select the three elements and press the OK button.
- Select species as well as the x- and y-axis.
- Press the Go to PSD button to see the diagram.
Labels can be relocated with the mouse; scales can be changed by pressing the Menu button; fonts can be changed by pressing the Font button, titles can be edited directly in the title fields.
If you want a paper copy of the diagram press the Print button and you will get a copy at the best resolution of any MS Windows - supported printer.
Eh - pH - Diagrams
Knowledge of the stabilities of ionic and non-ionic species in water solutions is critical to understanding problems of corrosion, dissolution, leaching and selective precipitation. This information can be displayed graphically by Eh - Ph - diagrams.
With this calculation option you can easily draw simple diagrams with only element and H2O as well as more complicated diagrams with several elements.
The dotted cyan lines indicate the stability area of water. Stability regions of ions can be outlined with blue lines, if necessary. Concentrations of the elements as well as scale settings can be changed by pressing the Menu button.
High resolution paper copies can be produced by pressing Print BW or Print Col buttons, as with the other calculation options.
HSC 6.0 is also now available:
The old HSC Chemistry? 5.1 software is made for the simulation and modeling of single chemical reactions and unit processes. The new HSC Chemistry?
6.0 will expand the scope of the old HSC 5.1 software to include the simulation and modeling of the whole process, made up of several unit processes.
HSC Chemistry 6.0 has many new features:
- The new Sim module with versatile auxiliary Data, Data-Fit and Geo modules
- Larger H, S and Cp database with more than 20 000 species (HSC 5.1 has 17 000 species). Several other fixes have also been made to the database
- New Excel Add-In interface with better compability with different Excel versions and different computers
- New Excel Add-In functions like StreamEQ for equilibrium calculations
- The printing and copy-paste options of the HSC modules has been improved
- The compatibility with Windows XP has been improved with several code changes and a new installation routine
- Working demo of the new GPS-based Material Map module
- Many other small bug fixes and new properties
- The familiar the HSC style, user interface and file formats have been maintained in order to minimize the training requirements for current HSC users.