A Study of the Homogeneous Vapour Phase Partial Oxidation of O-xylene

Abstract

<p> The homogeneous partial oxidation of ortho-xylene vapour by air in a 316 s.s. flow reactor was studied in this work, which was conducted in connection with, and preceding an investigation of the kinetics of catalytic vapour-phase partial oxidation of a-xylene. The main purpose of the present work was to make an exploratory study of the contribution of the homogeneous reaction, if any, in as much as it would affect the catalytic oxidation to be studied on the same experimental set-up. This would permit the correction for the rate of homogeneous reaction during the catalytic reaction under a range of experimental conditions, or, reveal conditions under which the catalytic reaction could be conducted with minimum contribution by the homogeneous reaction. </p> <p> The three variables studied and the range of conditions for each are as follows : 1. Air: o-xylene molar ratio: ,124 to J78 2. Residence time: 0.443 sec. to 0.539 sec. 3. Temperature: 430° C to 490° c </p> <p>The reaction product stream was analyzed mainly by Gas Chromatography, both qualitatively and quantitatively. Qualitative analyses of liquid samples of the reactor condensate were also conducted using a Nuclear Magnetic Resonance Spectrometer, Mass Spectrometer, Infrared Spectrophotometer and also by conventional chemical techniques. </p> <p> Product analysis indicated a-xylene oxide as the reaction product at the lmv conversions studied. An empirical correlation obtained by statistical analysis of the experimental data, relating the conversions obtained and the variables studied, has been proposed to calculate the extent of the homogeneous reaction under the conditions of a catalytic reaction study. The results obtained in this work are consistent with the suggested kinetics and mechanism for this reaction. </p>