Component Kinetics

Description

The Program is the software module for the kinetic evaluation of measurements with reactions in homogeneous mixtures. The total process is presented as the sum of elementary reactions. The software determines the pre-exponential factor and activation energy for each elementary reaction and makes the prediction and optimization of the reaction behaviour for any temperature conditions and for any initial concentration of reactants, including the presence of solvent.

Different data types can be evaluated; as long as they show distinct correlations to concentrations changes of the reactants.

  • Thermogravimetry (TGA),
  • Differential Scanning Calorimetry (DSC, DTA),
  • Mass spectrometry (MS)

The kinetic analysis allows the determination of the most probable reaction model as the sum of elementary reactions, the determination of the pre-exponential factor and activation energy for elementary reactions and then the prediction and optimization of the reaction behaviour for any temperature conditions.

The general interface to measurement data are ASCII files. In the program Component Kinetics the various methods of kinetic analysis and of predictions are integrated.

The predictions using the most probable kinetic model are assured only inside the tested ranges of time, temperature and concentrations, extrapolation can bring deviation from the real behaviour. Therefore the collective evaluation of isothermal and dynamic measurement data with the greatest possible range of heating rates and initial concentrations of reagents is not only wish-ful, but strong recommended. This is considered by Component Kinetics.

Verification of the program

For the following simple and complex mechanisms, important in chemistry, the results for heat flow and concentration were simulated by independent software:

  • Consecutive reactions
  • Competitive and independent parallel reactions
  • Equilibrium reactions
  • Combination of these basic types

In all cases the calculation was started with initial values of kinetic parameters having very big deviation from known results (and with big deviations of reaction enthalpy in case of heat flow curves). Neverthe-less, after calculation the expected values have been obtained and the observed deviation have been in the range of some tenth of a percent.

Thus here is the proof, that component kinetics is a valuable and reliable tool with the determina-tion of the model parameters and forecasts based on it. If the mechanism is unknown component kinetics can help to find the most probable reaction mechanism.

Special and Common Features

Special Features and Advantages in comparison with Software „Thermokinetics

  • Free formulation of the proposed reaction model by user as the set of elementary reactions
  • Direct input as concentrations of the reactants or calculation of its concentrations by the software after input of the corresponding masses
  • Direct input of reagent concentrations or calculation of concentrations by the software after input of corresponding masses
  • Considerably enhanced possibility to find the correct reaction model by the input of concentration curves for inter-mediate products, (see example 4)
  • Possibility to formulate reversible reaction steps as permanent equilibrium (preequilibria), if these steps are very fast in comparison with the remaining elementary reactions.
  • Simultaneous evaluation for reacting system
    • With variation of composition
    • Without solvent and/or with variation of kind and quantity of solvent
    • With variation of kind and quantity of catalysts and inhibitors
  • Taking into account volume changes during the reaction, if the densities of all reactants are known.
  • Taking into account the probable different functions of reactants
  • Simultaneous evaluation of up to 32 measurements, the reaction models can consist of up to 20 elementary steps

Common Features of Software "Component Kinetics" and "Thermokinetics"

  • Determination of the optimal kinetic parameters for all elementary reactions by using of non-linear regression
  • Predictions of the reaction behaviour for any combination of isothermal and dynamic temperature segments
    • Signal (DSC, TG)
    • Degree of conversion
    • Concentrations
  • User interface corresponds to the software „NETZSCH Thermokinetics

Applications

Application Fields

  • All fields of chemistry, biochemistry, material sciences
  • Fundamental research, applied research, process optimization and process control