Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported palladium catalyst

The syntheses of dimethyl oxalate （DMO） and diethyl oxalate （DEO） by CO coupling reaction in gaseous phase were investigated in a fixed bed reactor over Pd-Fe/ A1203 catalyst. The catalytic performance was characterized by CO conversion, space-time yield （STY） and selectivity of DMO （or DEO）. The results showed that over Pd-Fe/A1203 catalyst, the STY of DMO was higher than that of DEO under the same reaction conditions. The optimum reaction temperatures for synthesizing DMO and DEO were 403 K and 393 K, respectively, at the molar ratio 1：1 of alkyl nitrite to CO. The difference in synthesizing DMO and DEO on the same catalyst was attributed to the decomposition performances of methyl nitrite （MN） and ethyl nitrite （EN）, as density functional theory （DFT） calculation showed that EN decomposed more easily than MN.