The Cu–ZnO synergy in methanol synthesis from CO2, Part 2: Origin of the methanol and CO selectivities explained by experimental studies and a sphere contact quantification model in randomly packed binary mixtures on Cu–ZnO coprecipitate catalysts

CO2 Hydrogenation on Cu/Al2O3: Role of the Metal/Support Interface in Driving Activity and Selectivity of a Bifunctional Catalyst

“…Fori nstance,C uZn alloy or the Cu/ZnO interface has been proposed to generate the active site responsible for the high CH 3 OH selectivity. [37][38][39][40][41][42][43][44] In contrast, Al 2 O 3 ,aminor component of the catalyst, is typically viewed as as tabilizing oxide that maintains the dispersion of Cu and Zn. However, considering the high reactivity of alumina toward many small molecules,i ncluding CH 3 OH (see below), [45][46][47][48] for example, the dehydration of CH 3 OH to dimethyl ether (DME), [46] the involvement of alumina during the hydrogenation of CO 2 should be considered.…”

Fluorinated Cu/Zn/Al/Zr hydrotalcites derived nanocatalysts for CO2 hydrogenation to methanol

“…Furthermore, Cu/ZnO/Al 2 O 3 catalysts with promoter zirconia have demonstrated high performance in methanol synthesis from CO 2 hydrogenation due to the high copper dispersion and surface basicity [7][8][9]. However, the major competitive pathway of methanol synthesis is reverse water gas shift (RWGS) reaction, which leads to loss of methanol production [10,11]. A dual-site mechanism of CO 2 hydrogenation is widely accepted for the Cu/ZnO/Al 2 O 3 /ZrO 2 catalyst, which assumes that the atomic hydrogen transports from the surface of Cu onto the surface of ZnO-ZrO 2 sites via spillover and hydrogenates the adsorbed carbon-containing species to form methanol [7,12,13].…”

Microwave‐Assisted Hydrothermal Synthesis of CuO–ZnO–ZrO2 as Catalyst for Direct Synthesis of Methanol by Carbon Dioxide Hydrogenation

“…Notably,t he Cu crystallite sizes of the catalysts determined by using XRD vary slightly in ther ange of 18.4-21.0 nm, whereas there is al arge difference in S Cu assessed by measuring reactive N 2 Oa dsorption.T his is because S Cu dependso nt he Cu mass faction in the catalyst in additiont o the Cu crystallite size. [29] Another possible explanation is that there is ad ifference between the results obtained by using these two characterizationt echniques. [30,31] Fore xample, Słoczyń ski et al [30] reported that the sizes of Cu grains calculated from S Cu are 1.5-2.5 times larger than those obtained by using XRD.…”