1. Funda-
mentals
Thermo-
Dynamics
Kinetic
Data bases
Micro-
kinetics
Ab-initio
methods
Starting point: If you intend to perform a thorough investigation of the reaction kinetics, you should start
with the fundamental basis: search for thermodynamics and kinetic databases (if available). Additionally,
microkinetics and ab-initio modelling (e.g. using the DFT theory) could be considered.
2. Funda- Create reaction network
mentals Construct rate expressions
Initial parameer estimates
Thermo-
Dynamics
Kinetic
Data bases
Micro-
kinetics
Ab-initio
methods
Second step: The basic information is often prerequisite to allow to draw the reaction network, followed
by construction of the reaction rate equations and make rough estimates of the kinetic parameters to be
used as starting values in the parameter estimation. Besides open literature, information from
comparable systems are important sources of information.
3. Funda- Create reaction network
Reactor model
mentals Construct rate expressions Preferentially simple models
Also: Dynamic operation
Initial parameer estimates
Thermo-
Dynamics
Kinetic
Data bases
Micro-
kinetics
Ab-initio
methods
Modelling: The next step is to set up your reactor model, based on the conservation of momentum, mass,
and energy. In order to concentrate the effort on the reaction kinetics, these reactor models should be
preferentially simple (i.e. ideally stirred tank or plug-flow reactor). Non-steady state operation may be
considered to increase the amount of information about the reaction system.
4. Funda- Create reaction network
Reactor model
mentals Construct rate expressions Preferentially simple models
Also: Dynamic operation
Initial parameer estimates
Thermo-
Dynamics
New Experimental data
Kinetic (without transport limitations)
Data bases
Micro-
kinetics
Ab-initio
methods
Experimental work: After selecting a suitable test reactor and suitable test conditions at which one can
exclude disturbing phenomena such as transport limitations, non-homogeneous flow distribution, and
insufficient mixing can be excluded, a series of experiments should be carried out.
5. Funda- Create reaction network
Reactor model
mentals Construct rate expressions Preferentially simple models
Also: Dynamic operation
Initial parameer estimates
Thermo-
Dynamics Parameter estimation
New Experimental data
Kinetic (without transport limitations)
Data bases _
Micro-
+
kinetics
Ab-initio Reaction kinetics
methods
Parameter estimation: The unknown kinetic rate parameters are optimized to fit to the experimental data
as well as possible using a suitable software package, which should also provide proper statistical
information concerning the fit(s) obtained.
6. Funda- Create reaction network
Reactor model
mentals Construct rate expressions Preferentially simple models
Also: Dynamic operation
Initial parameer estimates
Thermo-
Dynamics Parameter estimation
New Experimental data
Kinetic (without transport limitations)
Data bases _
Micro-
+
kinetics Design of experiments
for: 1) Model discrimination
Ab-initio 2) Improving parameter Reaction kinetics
estimates
methods
Improving the kinetics: In many cases the fit obtained with the initial set of experiments yields too
unreliable kinetics. By using software suitable for (sequential) experimental design, you may determine
the most suitable experimental conditions for additional experiments to facilitate model discrimination
and to reduce the uncertainty ranges of the rate parameters.
7. Funda- Create reaction network
Reactor model
mentals Construct rate expressions Preferentially simple models
Also: Dynamic operation
Initial parameer estimates
Thermo-
Dynamics Parameter estimation
New Experimental data
Kinetic (without transport limitations)
Data bases _
Micro-
+
kinetics Design of experiments
for: 1) Model discrimination
Ab-initio 2) Improving parameter Reaction kinetics
estimates
methods
Effects of uncertainties
Translation to the production scale: An important but not easy step is to translate the remaining
uncertainties in the kinetic model obtained to the uncertainty in the performance of the large-scale
industrial reactor.
