Oscillatory dynamics in systems containing bromate and 1,4-cyclohexanedione in acidic media: I. The effect of temperature

Author(s)

Hyrla C. L. Oliveira ^[1] ; Tatiane B. Oliveira ^[2] ; Hamilton Varela ^[3]

Affiliation

^[1] Universidade de São Paulo. Instituto de Química de São Carlos - Brasil

^[2] Universidade de São Paulo. Instituto de Química de São Carlos - Brasil

^[3] Universidade de São Paulo. Instituto de Química de São Carlos - Brasil

• Document type: Journal article
• Source: Química Nova; v. 35, n. 2, p. 348-354, 2012-00-00.

Abstract

We present in this work the influence of temperature on the dynamics of homogeneous chemical systems containing bromate and 1,4-cyclohexanedione (1,4-CHD) in acidic media. In particular, the following systems were studied: bromate/1,4-CHD/acid, bromate/1,4-CHD/ferroin/acid and bromate/1,4-CHD/trisbipyridine ruthenium/acid. Investigations were carried out by means of an electrochemical probe, at five temperatures between 5 and 45 °C. Activation energies (Ea) were estimated in different ways for the pre-oscillatory and oscillatory regimes. In any case, the Ea was found to depend on the catalyst, composition and initial concentrations. In addition, it was observed that ferroin and trisbipyridine ruthenium act as catalysts only during the transition between the induction period and oscillatory regime. (AU)

• FAPESP's process: 08/08198-6 - Kinetic study of the bromate/hypophosphyte/CHD/dual catalysts system
• Grantee: Tatiane Barbosa de Oliveira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 09/07629-6 - Electrocatalysis IV: fundamental and applied aspects of electrocatalytic processes, bio-electrocatalysis and kinetic instabilities
• Grantee: Edson Antonio Ticianelli
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Thematic Grants