Kinetic model of ethylene oxidation in the presence of both ethylene dichloride (1,2-dichloroethane) and carbon dioxide over a highly selective silver catalyst

Experiments were conducted to obtain the kinetic model of ethylene oxidation over a commercial highly selective catalyst aAl(2)O(3)/Ag-Cs-Re, for the first time. A gas mixture of 4.15-7.5% O-2, 24.23% C2H4, 0-3.464% CO2, 0.56 ppm C2H4Cl2 and N-2 at 17.4 bar and 208-240 & nbsp;C was deployed, similar to that in industry. An adsorbed atomic oxygen and a gaseous ethylene molecule through modified or original Eley-Rideal mechanisms were responsible for both the partial and complete oxidation of ethylene. The partial oxidation engaged an additional uncovered active site in surface reaction compared to the complete oxidation. The surface reaction was the rate-limiting step under the experimental conditions. The proposed model is in remarkable agreement with the experimental data. The addition of CO2 to the feed was proved detrimental to the EO selectivity, only suppressing the EO production rate. Temperature raise was much in favor of the CO2 production rate, decreasing the EO selectivity. (C)& nbsp;2022 Elsevier Ltd. All rights reserved.

Automated summary

This study presents the kinetic model of ethylene oxidation over a commercial selective catalyst, aAl(2)O(3)/Ag-Cs-Re, for the first time. The results indicate that both partial and complete oxidation of ethylene occur through surface reactions, with the partial oxidation requiring additional active sites. The surface reaction is the rate-limiting step under the experimental conditions.