Complex dynamics in the bromate/hypophosphite/acetone/dual catalyst system

• Grant number: 05/03369-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2006
• End date: December 31, 2007
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Hamilton Brandão Varela de Albuquerque
• Grantee: Gustavo Tokoro Riether
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

New chemical systems have been recently designed for the study of complex phenomena such as oscillatory dynamics in the temporal domain and spatiotemporal pattern formation. Systems derived from oscillators based on the chemistry of bromate are the most extensively studied with the celebrated Belousov-Zhabotinsky (BZ) reaction being the most popular example. Problems such as the formation of bubbles (CO2) and solid precipitate in the course of the reaction and short-lived oscillations under batch conditions are very common and, in some cases, compromise the use of the some of these systems. The goal of the present project consists of the systematic study of the dynamic behavior of the bromate/hypophosphite/acetone/dual catalyst system. In spite of the superior properties previously attributed to this system, very little is known on the details of its dynamics. In this work, manganese and ferroin will be used as catalyst and the complete system (BrO3-/H2PO2-/acetone/Mn(II)-ferroin) will be studied under batch conditions. Temporal symmetry breaking will be studied in a reactor under agitation by means of the simultaneous records of the potential changes of platinum and Ag/AgBr electrodes, both measured versus a reversible hydrogen electrode. Experimental parameters such as the initial concentrations of some reactants will be varied and special attention will be devoted to the investigation of the role played by the acetone in the dynamics. Additionally, spatio-temporal formation will be studied in a quasi two-dimensional reactor. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GUSTAVO TOKORO; HYRLA C. L. OLIVEIRA; HAMILTON VARELA. Dinâmica complexa no sistema bromato/hipofosfito/acetona/manganês e ferroína. Química Nova, v. 30, n. 8, p. 1930-1937, 2007-00-00. (05/03369-9)