Methanol and C2 oxygenate synthesis over cesium doped Cu/ZnO and Cu/ZnO/Al2O3 catalysts: A study of selectivity and 13C incorporation patterns

Oxygenates vs. synthesis gas

“…Doping with heavy alkali is known to enhance the activity of Cu/ZnO catalysts [Klier et al, 1984;Nunan et al, 1986;Bybell et al, 1986;Nunan et al, 1988;. The present study has demonstrated the large enhancement of methanol productivity of Cu/ZrOz catalysts bycesium doping.…”

“…Another possible contribution to the observed lower catalyst activity in the water injection experiment might be the formation of iron carbonyl, which is known to cause catalyst deactivation [Bogdan et al, 1988]. During the water injection, the injection port was heated to approximately 393-423K, which may have been high enough to induce iron carbonyl formation.…”

“…It was found that methanol yields could be greatly enhanced by the addition of small amounts of C02 and H20 to the synthesis gas feed Vedage et al, 1984a;Vedage et al, 1984b]. Doping Cu/ZnO catalysts with cesium has also been reported to increase the productivities of methanol and higher alcohols, especially isobutanol [Nunan et al, 1988;Nunan et al, 1986;Bybell et al, 1986;Klier et al, 1984].…”

“…Catalyst. Since cesium doping is known to enhance the productivity of methanol over Cu/ZnO catalysts [Klier et al, 1984;Nunan et al, 1986;Bybell et al, 1986;Nunan et al, 1988], this effect was investigated over the Cu/Zr02 = 10/90 catalyst by doping the catalyst with 3 mol% Cs. Data obtained from both the doped and undoped 10/90 Cu/Zr02 catalysts as a function of reaction temperature are presented in Figure 10.…”

“…Efforts have been made to understand the nature of the catalytically active sites, as well as the mechanism of methanol and higher alcohol formation Mehta et al, 1979;Takahama et al, 1983;Bridgewater et al, 1983;Friedrich et al, 1983;Fleisch and Mieville, 1984;Klier et al, 1988;Nunan et al, 1988;Nunan et al, 1989a;Nunan et al, 1989b;Klier et al, 1993]. It was found that methanol yields could be greatly enhanced by the addition of small amounts of C02 and H20 to the synthesis gas feed Vedage et al, 1984a;Vedage et al, 1984b].…”