Gas-phase kinetic and mechanistic investigation of the OH radical and Cl atom oxidation of tetraethoxysilane

摘要

Rate coefficients have been determined in a large photoreactor for the reaction of OH radicals and Cl atoms with tetraethoxysilane (TEOS, (CH3CH2O)(4)Si) using a relative kinetic method and in situ FTIR spectroscopy for the analysis. Values of (2.99 +/- 0.37) x 10(-11) and (2.41 +/- 0.47) x 10(-10) cm(3) per molecule per s were obtained for the reactions of OH and Cl with TEOS, respectively, at 298 K and atmospheric pressure. The products originating from the OH-radical and Cl-atom initiated oxidation of TEOS have also been investigated. Acetic acid (CH3C(O)OH) is observed as a major product in both cases with a molar yield of (95 +/- 4)%. An oxidation mechanism is proposed to explain its formation and the possible identity of the co-product(s) is discussed.