Kinetics of the Bray-Liebhafsky oscillatory reaction perturbed by polymer supported cobalt catalyst

J.P Maksimovic,D Loncarevic,Z.D Cupic,N Pejic,D Vasiljevic-Radovic,S Anic

doi:10.2298/sos1101055m

Abstract

The Bray-Liebhafsky (BL) oscillatory reaction generated in the batch reactor at 62- 68 oC was perturbed by cobalt(II)-nitrate, supported on the macroreticular copolymer of poly-4-vinylpyridine with divinylbenzene (Co-PVPDVB). The kinetic data was analyzed of the complex pathways of the hydrogen peroxide decomposition in the examined BL reaction. The obtained results confirm that the kinetics of the BL reaction in the presence Co-PVPDVB comes partially from the Co-catalyst and partially from the macroreticular copolymer support.

Highlights

The oscillatory reactions as analytical matrix were used from about twenty years ago [1,2,3,4,5]
We found that polymer support has stronger influence on kinetic parameters τ1 and τend than the catalyst, and changes were in the same direction
It was proven that most cobalt ions from catalyst Co-PVPDVB are extracted in acidified aqueous medium of the BL reaction and polymer support, PVPDVB, is itself strongly perturbing agent

Summary

Introduction

The oscillatory reactions as analytical matrix were used from about twenty years ago [1,2,3,4,5]. The Bray-Liebhafsky oscillatory reaction [6, 7] has been successfully applied as sensitive matrix for the characterization of catalysts [5, 8,9,10,11,12,13]. It was found that there is a correspondence between the rate constants kR and kO in reactions R and O, and characteristic kinetic parameters such as τ1 (preoscillatory period) and τend (duration of the oscillogram): kR. That the kinetics of the overall reaction D is controlled by reaction O. [14,15,16,17,18] These relations are useful for the kinetic analysis of the perturbed BL matrix by any small perturbation. [19]

Experimental

Results and Discussion

BL filtrate

Conclusion