A kinetic study of Pd-Au catalyzed synthesis of vinyl acetate from oxidation of ethylene and acetic acid in heterogeneous gas reaction

作者：Motahari Kazem^*; Atashi Hossein; Fazlollahi Farhad; Tabrizi Farshad F; Sarkari Majid

来源：Journal of Industrial and Engineering Chemistry, 2012, 18(1): 266-271.

DOI：10.1016/j.jiec.2011.11.036

• Kinetics
• Vinyl acetate
• Pd-Au/SiO2 Catalyst
• Fixed-bed reactor

While qualitative interpretation of the experimental results is often limited to the identification of global mechanistic phenomena, kinetic modeling is a more powerful tool for the identification of the chemical reaction network that can describe the experimental results. In this paper, kinetic study of vinyl acetate (VA) synthesis was performed in a fixed bed reactor with oxidation of ethylene and acetic acid in gaseous phase over Pd/Au/SiO2 catalyst under the industrial relevant reaction condition as follows: temperature of 120-165 degrees C, at constant pressure of 8 bar and the ratio of catalyst mass to the feed (W/F) was maintained at 70 g/mol min. Variation in partial pressure and concentration of reactants have led us to determine the rate limiting step and therefore proposing a new rate low based on Langmuir-Hinshelwood-Hougen-Watson (LHHW) approached consistent with experimental observation while adapted through mathematical formulation with high reliance. So, the kinetic parameters were determined by the Levenberg-Marquardt algorithm. Effect of temperature has also been surveyed showing a decreased in selectivity due to the difference in reaction constants of main and side reaction rate and an increase rate due to the increase in apparent activation energy.

• 出版日期2012-1-25