Title

Nonlinear instabilities in photochemical oxidations of 1,4-cyclohexanedione and its derivatives.

Date of Award

2006

Degree Type

Thesis

Degree Name

M.Sc.

Department

Chemistry and Biochemistry

Keywords

Chemistry, Physical.

Rights

CC BY-NC-ND 4.0

Abstract

In the closed 1,4-cyclohexanedione(CHD) bromate oscillatory reaction, we discovered that stirring can induce transitions between simple and period-doubled oscillations. When illumination was employed to characterize the importance of micro fluctuations of concentrations, the threshold stirring rate for inducing a bifurcation was found to increase proportionally to the intensity of the applied light. Numerical simulations with an existing model illustrate that the experimental phenomena could be qualitatively reproduced by considering effects of mixing on diffusion-limited radical reactions, namely, the disproportion reaction of hydroquinone radicals. A novel light-mediated chemical oscillator, i.e. 1,4-benzoquione(Q-bromate oscillator, was uncovered and investigated systematically in a batch reactor. Dependence of the oscillatory dynamics on the intensity of illumination was characterized. Quenching experiments suggest that the bromate - 1,4-Q oscillator is not only Br- controlled, but also radical-controlled. Oscillations were also investigated in a CSTR system. A mechanism was proposed, which successfully reproduced the experimental phenomena.Dept. of Chemistry and Biochemistry. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2006 .Z44. Source: Masters Abstracts International, Volume: 45-01, page: 0330. Thesis (M.Sc.)--University of Windsor (Canada), 2006.