KINETIC-STUDY OF THE CE(III)-CATALYZED OR FERROIN-CATALYZED BELOUSOV-ZHABOTINSKY REACTION WITH ETHYL-MALONIC OR BUTYL-MALONIC ACID

In a stirred batch experiment, ferroin (Fe(phen)(3)(2+)) behaves diffe rently from Ce(III) as a catalyst for the Belousov-Zhabotinsky reactio n with ethyl- or n-butyl-malonic acid (EtMA or BuMA). The effects of b romate ion, organic substrate, metal-ion catalyst, and sulfuric acid o n the oscillating pattern were investigated. The kinetics of the react ions of methylmalonic acid (MeMA), bromomethyl-malonic acid (BrMeMA), EtMA, bromoethylmalonic acid (BrEtMA), BuMA, bromo(n-butyl)malonic aci d (BrBuMA) with Ce(IV) or Fe(phen)(3)(3+) ion were studied. Under aero bic or anaerobic conditions, the order of reactivity toward Ce(IV) oxi dation is MeMA > EtMA > BuMA > BrMeMA much greater than (BrEtMA, BrBuM A). Under aerobic conditions, the order of reactivity toward reacting with Fe(phen)(3)(3+) ion is MeMA > (BuMA, EtMA) much greater than (BrM eMA, BrEtMA, BrBuMA). The experimental results are rationalized. (C) 1 996 John Wiley & Sons, Inc.