The role of Ce(III) in BZ oscillating reactions

• Published in: Chemical physics letters Vol. 530; pp. 137 - 139
• Main Authors: Nogueira, Paulo A., Varela, Hamilton, Faria, Roberto B.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 19.03.2012
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2012.01.066

[Display omitted] ► No oscillations are observed in a CSTR on the bromate–oxalic acid–acetone–Ce(IV) system. ► Ce(III) is the only catalyst necessary to produce oscillations on this system. ► When Ce(IV) is used, the induction period is a time necessary to convert Ce(III) to Ce(IV). Herein we present results on the oscillatory dynamics in the bromate–oxalic acid–acetone–Ce(III)/Ce(IV) system in batch and also in a CSTR. We show that Ce(III) is the necessary reactant to allow the emergence of oscillations. In batch, oscillations occur with Ce(III) and also with Ce(IV), but no induction period is observed with Ce(III). In a CSTR, no oscillations were found using a freshly prepared Ce(IV), but only when the cerium-containing solution was aged, allowing partial conversion of Ce(IV) to Ce(III) by reaction with acetone.