On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system

The oscillatory picric acid/CTAB two-phase system-as introduced by Yoshikawa and Matsubara [J. Am. Chem. Soc. 1984, 106, 4423-4427]-has been revisited. UV-vis spectroscopic studies were presented that provide a clearer and new insight into the possible kinetic mechanism for the oscillatory behavior....

Descripción completa

Detalles Bibliográficos
Autores principales: Pimienta, V., Etchenique, R., Buhse, T.
Formato: JOUR
Materias:
Alcohols
Computer simulation
Electrochemistry
Interfaces (materials)
Ions
Oscillations
Reaction kinetics
Ultraviolet spectroscopy
Electrochemical oscillations
Organic acids
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_10895639_v105_n44_p10037_Pimienta
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id todo:paper_10895639_v105_n44_p10037_Pimienta
record_format dspace
spelling todo:paper_10895639_v105_n44_p10037_Pimienta2023-10-03T16:04:28Z On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system Pimienta, V. Etchenique, R. Buhse, T. Alcohols Computer simulation Electrochemistry Interfaces (materials) Ions Oscillations Reaction kinetics Ultraviolet spectroscopy Electrochemical oscillations Organic acids The oscillatory picric acid/CTAB two-phase system-as introduced by Yoshikawa and Matsubara [J. Am. Chem. Soc. 1984, 106, 4423-4427]-has been revisited. UV-vis spectroscopic studies were presented that provide a clearer and new insight into the possible kinetic mechanism for the oscillatory behavior. It was shown that the key process in the system is the formation of 1:1 ion pairs between picrate and CTA+ at the liquid/liquid interface that desorb and move into the organic phase. Kinetic UV-vis experiments also showed that the presence of alcohol-which was essential to observe oscillatory behavior-inhibits the formation of ion pairs. In the course of this process, this inhibition is released presumably due to the transfer of the alcohol from the interface into the organic phase. The corresponding inhibition/acceleration dynamics were observed in a subsystem experiment as S-shaped, autocatalytic-like kinetics with respect to the ion-pair formation. A new mechanism based on Langmuir-Hinshelwood kinetics was proposed that includes the competitive adsorption of CTA+, picrate, and the alcohol at the liquid/liquid interface. The release of inhibition, which depends on the concentration of vacant interface sites and which occurs autocatalytically, expresses the key process for the nonlinear behavior. Computer simulations were performed which confirm that the proposed kinetic mechanism is dynamically reasonable. Fil:Etchenique, R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_10895639_v105_n44_p10037_Pimienta
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Alcohols
Computer simulation
Electrochemistry
Interfaces (materials)
Ions
Oscillations
Reaction kinetics
Ultraviolet spectroscopy
Electrochemical oscillations
Organic acids
spellingShingle Alcohols
Computer simulation
Electrochemistry
Interfaces (materials)
Ions
Oscillations
Reaction kinetics
Ultraviolet spectroscopy
Electrochemical oscillations
Organic acids
Pimienta, V.
Etchenique, R.
Buhse, T.
On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system
topic_facet Alcohols
Computer simulation
Electrochemistry
Interfaces (materials)
Ions
Oscillations
Reaction kinetics
Ultraviolet spectroscopy
Electrochemical oscillations
Organic acids
description The oscillatory picric acid/CTAB two-phase system-as introduced by Yoshikawa and Matsubara [J. Am. Chem. Soc. 1984, 106, 4423-4427]-has been revisited. UV-vis spectroscopic studies were presented that provide a clearer and new insight into the possible kinetic mechanism for the oscillatory behavior. It was shown that the key process in the system is the formation of 1:1 ion pairs between picrate and CTA+ at the liquid/liquid interface that desorb and move into the organic phase. Kinetic UV-vis experiments also showed that the presence of alcohol-which was essential to observe oscillatory behavior-inhibits the formation of ion pairs. In the course of this process, this inhibition is released presumably due to the transfer of the alcohol from the interface into the organic phase. The corresponding inhibition/acceleration dynamics were observed in a subsystem experiment as S-shaped, autocatalytic-like kinetics with respect to the ion-pair formation. A new mechanism based on Langmuir-Hinshelwood kinetics was proposed that includes the competitive adsorption of CTA+, picrate, and the alcohol at the liquid/liquid interface. The release of inhibition, which depends on the concentration of vacant interface sites and which occurs autocatalytically, expresses the key process for the nonlinear behavior. Computer simulations were performed which confirm that the proposed kinetic mechanism is dynamically reasonable.
format JOUR
author Pimienta, V.
Etchenique, R.
Buhse, T.
author_facet Pimienta, V.
Etchenique, R.
Buhse, T.
author_sort Pimienta, V.
title On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system
title_short On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system
title_full On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system
title_fullStr On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system
title_full_unstemmed On the origin of electrochemical oscillations in the picric acid/CTAB two-phase system
title_sort on the origin of electrochemical oscillations in the picric acid/ctab two-phase system
url http://hdl.handle.net/20.500.12110/paper_10895639_v105_n44_p10037_Pimienta
work_keys_str_mv AT pimientav ontheoriginofelectrochemicaloscillationsinthepicricacidctabtwophasesystem
AT etcheniquer ontheoriginofelectrochemicaloscillationsinthepicricacidctabtwophasesystem
AT buhset ontheoriginofelectrochemicaloscillationsinthepicricacidctabtwophasesystem
_version_ 1807319529001320448

Ejemplares similares