Iodide-ion-induced oscillations of the ferroin-catalyzed Belousov—Zhabotinskii reaction

✍ Scribed by Milan Melicherčík; Ľudovít Treindl

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 206 KB
• Volume: 196
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(92)85921-v

✦ Synopsis

Contrary to "classical" Belousov-Zhabotinskii (BZ) oscillatory systems, consisting of malonic acid, Ce (IV) -Ce (III) or Mn (III) -Mn (II) redox catalyst and KBrOa in solutions of H2SO4, where in an interval of added iodide initial concentrations 10 -4 mol din-3< [I-]o< 10 -a tool dm -3 the oscillalions have the same frequency and amplitude as in the absence of iodide, the effect of added iodide on the ferroin-eatalyzed BZ system with methyl ester of 3-0xobutanoic acid leads to an increase in the number of oscillations and in the time of their duration. The dependence of this effect on substrate, bromate, iodide, sulfuric acid and ferroin concentrations has been studied. The observations may be explained by a mechanism involving direct reduction of ferroin by iodide, oxidation of iodide to iodate by brornate with a bromide production and eventual faster bromination and iodination of methyl ester of 3-0xobutanoic acid in relation to malonic acid.