Selective synthesis of gasoline from syngas in near-critical phase

Selective Synthesis of Gasoline-Ranged Hydrocarbons from Syngas over Hybrid Catalyst Consisting of Metal-Loaded ZSM-5 Coupled with Copper-Zinc Oxide

“…When 3 wt% Cu species was loaded on ZSM-5, the rapid deactivation was obviously suppressed compared with 0 wt% and 1 wt% Cu/ZSM-5, resulting in the CO conversion of 65% after 6.5 h of the reaction time. The inhibition of the deactivation by loading the Cu species on ZSM-5 is consistent with the previous report employing hybrid catalysts with Pd/ZSM-5 [15,20]. By contrast, a further increase in the Cu loading caused the deactivation at the initial periods of the reaction again; in addition, decreased the CO conversion.…”

“…In order to investigate the durability of the hybrid catalyst with Cu/ZSM-5 in the syngas conversion, the changes in the CO conversion and product selectivities along with time-on-stream were examined in a long-run reaction at 553 K. It is reported that by loading Pd on ZSM-5, a high CO conversion was retained without the rapid deactivation and changes in product distributions in the conversion of syngas to the gasoline-ranged hydrocarbons [15]. As shown in Figure 6, the initial CO conversion of the hybrid catalyst with 0.5 wt% Pd/ZSM-5 reached to 80%, while the hybrid catalyst with 5 wt% Cu/ZSM-5 exhibited 77% initial CO conversion.…”

“…A pressurized flow type of reaction apparatus with a fixed-bed reactor was used for this study to carry out catalytic reaction tests following our previous reports [15,20]. The experimental set-up scheme is shown in Figure 7.…”

“…In addition, the hydrogenation by the metal species is expected to decompose carbonaceous species to suppress the deposition of heavy coke in/on the zeolite, leading to longevity of the catalyst. Recently, we have reported that the hybrid catalyst consisting of Cu-ZnO coupled with Pd/ZSM-5 exhibited a slow deactivation with a comparative yield of gasoline-ranged hydrocarbons compared with the hybrid catalyst with H-ZSM-5 in the conversion of syngas to hydrocarbons through the formation of methanol [15].…”

“…We have previously reported that a near-critical n-hexane solvent improved the yield of hydrocarbons in the syngas conversion to hydrocarbons via methanol over the hybrid catalyst consisting of Cu-ZnO and the Pd-loaded zeolite because of a good heat transfer in the reaction system under the near-critical solvent flowing [15,20]. In this study, we investigated the catalytic activity of hybrid catalysts composed of Cu-ZnO and metal-loaded ZSM-5 in a near-critical n-hexane solvent in the conversion of syngas to hydrocarbons via methanol.…”