Optimization of synthesis condition for CO2 hydrogenation to light olefins over In2O3 admixed with SAPO-34

Abstract

Recycling of CO2 into light olefins offers opportunity to mitigate CO2 emissions, while decreasing dependence on fossil fuels for light olefins production. Herein, we report on the direct conversion of CO2 to light olefins over a hybrid catalyst containing In2O3 admixed with SAPO-34. The effect of mass ratios of In2O3 to SAPO-34 and operating conditions including reaction temperature, reaction pressure and space velocity for maximizing light olefins yield was thoroughly studied. The results show that the interplay of active sites for CO2 hydrogenation (In2O3) and methanol transformation (SAPO-34), and operating conditions are a key factor determining the catalytic behavior. The best yield of light olefins (7.31%) with a CO2 conversion of 34.6% is achieved over the In2O3/SAPO-34 catalyst with a mass ratio of 2:1 at 360 °C, 25 bar and 1,500 mL gcat−1 h−1.