Stoichiometric Models

M. Amrhein, B. Srinivasan and D. Bonvin
Completed project (1990, 1999)

A methodology was developed to identify stoichiometric models of complex reaction systems. In a first research campaign, a methodology was developed to derive the number of independent reactions and the corresponding stoichiometric model, without any prior knowledge of reaction kinetics. In a second campaign, it was shown how this methodology could be combined with pre-treated data and reaction-invariants relationships.

Identification of Stoichiometric Models

D. Bonvin (1990)

In this work, an approach was developed for (1) deriving simple, approximate stoichiometric models for complex systems, or (2) testing possible stoichiometries and thereby investigating reaction pathways. The method, which is based on Target Factor Analysis (TFA), was used to determine the number of independent reactions and derive an observed stoichiometric space from measured composition and possibly thermal data. The approach is straightforward with noise-free data and various ways of coping with measurement errors have been proposed. The major contribution of this work consisted in an approach for incorporating known stoichiometric information, thereby reducing considerably the effect of measurement noise. The methodology was tested on a simulated model of an industrial system.

Data Pre-treatment and Reaction-Invariant Relationships

M. Amrhein, B. Srinivasan and D. Bonvin (1999)

This work analyzed the applicability of TFA techniques to reaction data on the basis of concentration measurements. It was shown that, in some cases, a data matrix that is well suited to existing TFA techniques could be constructed from concentration measurements, material exchange terms, and initial conditions (data pre-treatment). Otherwise, TFA needed to be performed directly on the measured concentration data. In the latter scenario, knowledge of reaction-invariant relationships was required to specify necessary and sufficient conditions for the acceptance of stoichiometric targets. The case of unmeasured species was also investigated.


Target factor analysis; Analysis of reaction data; Stoichiometric models; Reaction invariants


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