Older Chemical Oscillators

Prior to our systematically designed oscillators, the inorganic oscillator most intensively studied was the BZ reaction. Examination of this reaction and the FKN mechanism reveals several features helpful to achieving an appreciation for the construction of a chemical oscillator. The driving force for the BZ reaction is the reduction of bromate and the associated oxidation of malonic acid (MA) to carbon dioxide. The stoichiometry is not that simple, however, since bromomalonic acid is also produced in the reaction, and can be oxidized to formic acid. A possible stoichiometry is 

3BrOj + 5 CH2(COOH)2 + 3H+-------— 3BrCH(COOH)2 + 2HCOOH + 4C02 + 5H20 (I) 

2Br03- + 3CH2(COOH)2 + 2H+ 2BrCH(COOH)2 + 3C02 + 4H20 

Although bromate is a powerful oxidizing agent, it is kinetically inert. Reaction (I) occurs at a resonable rate because of the generation of reactive bromine-containing 

Although the BL reaction contains no organic compounds, the list of reactions to be considered is lengthy and complicated. For example, O2 has to be considered as aquated (i.e., dissolved) reaction intermediate, and as gaseous product. Nevertheless, the principles of the FKN mechanism have been applied to the BL reaction with some success23, though a number of questions still remain about certain details of the mechanism24. The mechanism contains a non-radical process, 

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