Study On Macro-kinetics Of CO Catalytic Coupling Reaction To Diethyl Oxalate In Gaseous Phase At Low-pressure

The coupling reaction of carbon monoxide to produce diethyl oxalate (DEO) in gaseous phase is an important subject of C1 chemical technology. It's very significant in the process substutided for conventional production of oxalate ester, oxalate acid, ethylene glycol and intermediates for pharmaceuticals and dyestuffs.The synthesis of diethyl oxalate from carbon monoxide and ethyl nitrite which was carried out on the supported palladium bimetal catalyst was studied in a continuous flow fixed-bed reactor at low-pressure. The effect of temperature, residence time, the mole concentration of ethyl nitrite (EN) and CO and the pressure on the reaction were studied. The results showed that the activity and stability of the catalyst had reached the level of industrial application in the condition of the temperature 90℃~ 130℃, the residence time 1.5 s~3 s, the pressure 0.1 MPa~0.3 MPa, EN molar concentration 10%~20%, CO molar concentration 20%~30%. The STY of DEO was 578 g/(L·h) at 130℃and 0.3 MPa with residence time 1.5 s and molar concentration of EN and CO 20%.This work aimed mainly at the micro-kinetics study of the coupling reaction of the synthesis of diethyl oxalate and it's side reaction, the formation of diethyl carbonate (DEC), in vapor phase at low-pressure from CO. The reaction model of power function type was established both for the formation of DEO and DEC by the one dimensional pseudo homogenous reactor model. By optimization of the results in different reaction conditions, the parameters of the macro-kinetics were determined. The equations of the kinetics were as follows:...