Setting up In₂O₃-ZrO₂/SAPO-34 Catalyst for Improving Olefin Production via Hydrogenation of CO₂/CO Mixtures

Abstract

The adequate configuration and the effect of the reduction was studied for the In2O3-ZrO2/SAPO-34 catalyst with the aim of improving its performance (activity and selectivity in the pseudo-steady state) for the hydrogenation of CO, CO2 and CO2/CO (COx) mixtures into olefins. The experiments were carried out in a packed bed reactor at 400 °C; 30 bar; a H2/COx ratio of 3; CO2/COx ratios of 0, 0.5 and 1; a space time (referred to as In2O3-ZrO2 catalyst mass) of 3.35 gInZr h molC−1; and a time on stream up to 24 h. The mixture of individual catalyst particles, with an SAPO-34 to In2O3-ZrO2 mass ratio of 1/2, led to a better performance than hybrid catalysts prepared via pelletizing and better than the arrangement of individual catalysts in a dual bed. The deactivation of the catalyst using coke deposition and the remnant activity in the pseudo-steady state of the catalyst were dependent on the CO2 content in the feed since the synergy of the capabilities of the SAPO-34 catalyst to form coke and of the In2O3-ZrO2 catalyst to hydrogenate its precursors were affected. The partial reduction of the In2O3-ZrO2/SAPO-34 catalyst (corresponding to a superficial In0/In2O3 ratio of 0.04) improved its performance over the untreated and fully reduced catalyst in the hydrogenation of CO to olefins, but barely affected CO2/CO mixtures’ hydrogenation.

Keywords

• CO₂
• In₂O₃ catalyst
• SAPO-34 catalyst
• methanol synthesis
• olefin synthesis
• coke deactivation