| Summary: | The adequate configuration and the effect of the reduction was studied for the In<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub>/SAPO-34 catalyst with the aim of improving its performance (activity and selectivity in the pseudo-steady state) for the hydrogenation of CO, CO<sub>2</sub> and CO<sub>2</sub>/CO (CO<sub>x</sub>) mixtures into olefins. The experiments were carried out in a packed bed reactor at 400 °C; 30 bar; a H<sub>2</sub>/CO<sub>x</sub> ratio of 3; CO<sub>2</sub>/CO<sub>x</sub> ratios of 0, 0.5 and 1; a space time (referred to as In<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub> catalyst mass) of 3.35 g<sub>InZr</sub> h mol<sub>C</sub><sup>−1</sup>; and a time on stream up to 24 h. The mixture of individual catalyst particles, with an SAPO-34 to In<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub> 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 CO<sub>2</sub> content in the feed since the synergy of the capabilities of the SAPO-34 catalyst to form coke and of the In<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub> catalyst to hydrogenate its precursors were affected. The partial reduction of the In<sub>2</sub>O<sub>3</sub>-ZrO<sub>2</sub>/SAPO-34 catalyst (corresponding to a superficial In<sup>0</sup>/In<sub>2</sub>O<sub>3</sub> ratio of 0.04) improved its performance over the untreated and fully reduced catalyst in the hydrogenation of CO to olefins, but barely affected CO<sub>2</sub>/CO mixtures’ hydrogenation.
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