0000000000582739
AUTHOR
Krisztina Pelle
The Source of the Carbon Monoxide in the Classical Belousov-Zhabotinsky Reaction
CO and CO2 evolution was measured in a cerium and in a ferroin-catalyzed Belousov−Zhabotinsky (BZ) reaction. These gases were stripped from the reaction mixture by a N2 carrier gas, mixed with H2, converted to methane on a Ni catalyst, and then measured by a flame ionization detector (FID). CO could be detected separately by absorbing CO2 on a soda lime column. In separate experiments it was proven that CO is produced in a reaction of BrO2• radicals with bromomalonic acid (BrMA). To this end BrO2• radicals were generated in two different ways: (i) in the reaction HBrO2 + HBrO3 ↔ 2 BrO2• + H2O and (ii) by reducing HBrO3 to BrO2• by Fe2+. It was found that •OH radicals produced by Fenton's r…
Mechanistic Investigations of the BZ Reaction with Oxalic Acid Substrate. I. The Oscillatory Parameter Region and Rate Constants Measured for the Reactions of HOBr, HBrO2, and Acidic BrO3- with Oxalic Acid
This paper is the first part of a study reinvestigating the mechanism of the Belousov-Zhabotinsky (BZ) reaction of oxalic acid, which is the simplest organic substrate for a BZ oscillator. New experiments are performed to find the oscillatory region in 1 M sulfuric acid at 20 °C. The removal rate of the end product bromine by an inert gas stream is a critical parameter here: oscillations can be observed only in a window of that parameter. The “rate constant” for the physical removal of bromine is measured as a function of the gas flow rate and reactor volume; furthermore, the rate constants of three component reactions important in this system are also determined. These are oxygen atom tran…