Estratégias para ajuste de perfis de concentração para cálculo das taxas de reação

Marcelo Segala Xavier; Esly Ferreira da Costa Junior

doi:10.22481/exon.v13i2.20575

Authors

Marcelo Segala Xavier Universidade Federal de Minas Gerais
Esly Ferreira da Costa Junior Universidade Federal de Minas Gerais

DOI:

https://doi.org/10.22481/exon.v13i2.20575

Keywords:

parameter estimation, optimization, concentration profiles, chemical kinetics

Abstract

Among the various existing methods to calculate the reaction rates of concentration data as a function of time, many have inherent errors in the procedure or may present contradictions related to the experiment. This study presents an approach to concentration profiles fitting method in order to calculate reaction rates by differentiating the obtained function. Therefore, a set of kinetic data from the literature was used. Intending to minimize errors and problems, several ways of fitting were tested: initially, polynomial regression was performed, which provided estimates that were inconsistent with the experiments. Then, the possibility of restricting the polynomial regression with known physical information was tested, solving it as a restricted optimization problem, however, the obtained profiles presented inconsistencies in relation to the experiments. At last, a different strategy was used: doing regression by solving an optimization problem in which the model was compatible with the experimental data trends. The results achieved proved to be highly representative and did not present nonconformities in comparison with the experimental data.

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