Kinetics of Photoresponse of the Chlorine Dioxide-Iodine-Malonic Acid Reaction

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Vol. 104; no. 24; pp. 5766 - 5769
• Main Authors: Horváth, Attila K, Dolnik, Milos, Zhabotinsky, Anatol M, Epstein, Irving R
• Format: Journal Article
• Language: English
• Published: American Chemical Society 22-06-2000
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp000352s

We studied the photoresponse of the chlorine dioxide−iodine−malonic acid (CDIMA) reaction. In a continuously fed stirred tank reactor, the photosensitivity increases with decreasing residence time and increasing concentration of chlorine dioxide. Under certain conditions, concentrations change in a sigmoidal fashion in response to a jump in the intensity of illumination. We propose a new mechanism for the effect of visible light on the CDIMA reaction. Simulations based on the proposed mechanism accurately describe the experimentally observed kinetics.