PRODUCTION OF LIGHT OLEFINS FROM CO2 HYDROGENATION OVER Fe/SILICALITE-2 CATALYST III. PROMOTION EFFECT OF K2O PROMOTER

K2O is a vital promoter to the Fe-MnO/silicalite-2 catalyst for light olefin formation from CO2 hydrogenation. With addition of it into the Fe-MnO/Si-2 catalyst the selectivity to light olefins increases greatly, while CH4 formation is inhibited evidently. Meanwhile, an obvious increment in CO2 conversion is also observed with the addition of K2O promoter. And it has been manifested that adding K2O to the Fe-MnO/Si-2 catalyst leads to remarkable increases in both the capacity and strength of the strong CO2 and CO adspecies. These produce much moreCad] via their disproportionation at higher temperatures. This results in increase in the CO2 conversion and the selectivity to light olefins, and a decrease in CH4 formation.