COMBINED KINETIC RESPONSE OF TWO SUBSTRATES WITH SIMILAR REACTIVE PATTERNS
Date
2017-03-30
Authors
Dana Maria SABOU
Alexandra Ana CSAVDÁRI
Journal Title
Journal ISSN
Volume Title
Publisher
STUDIA UBB CHEMIA. Published by Babeş-Bolyai University
Abstract
The behaviour towards simultaneous oxidation by Cr(VI) in acidic environment of mixtures consisting of two structurally closely related thioethers (S-methylcysteine and DL-methionine) was tested, at 0.085 mol·l-1 H+ and 298 ± 0.1 K. The kinetic and mechanistic patterns of the two substrates when oxidized separately were already known and very similar. Based on that knowledge, the individual kinetic parameters (rate and equilibrium constants) were first computed. Theoretical predictive models for the value of the observed rate constant of a mixture, based on the kinetic data from non-mixtures, are compared with experimental findings and subsequently an empirical calibration surface obtained from all experiments is discussed. Due to differences in the kinetic parameters of the two reactions, in all models the obtained surfaces are asymmetrical, and this opens the possibility to univocally determine the concentrations of both thioethers, without separation.
Description
STUDIA UBB CHEMIA, LXII, 1, 2017 (p. 19-33), DOI:10.24193/subbchem.2017.1.02
Dana Maria SABOU
Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Cluj-Napoca, Romania, dana.sabou@ubbcluj.ro
https://orcid.org/0000-0001-6199-6081
Alexandra Ana CSAVDÁRI
Department of Chemical Engineering, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University of Cluj-Napoca, Romania.
*Corresponding author: alexandra.csavdari@ubbcluj.ro
https://orcid.org/0000-0003-4321-5610
Keywords
chromium VI oxidation, DL-methionine, S-methylcysteine, combined kinetic response, kinetic modeling
Citation
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