Copper based catalysts (Cu–ZnO/Al2O3) containing various Cu/Zn weight ratios
were prepared by coprecipitation. The XRD measurements of the catalysts reveal
the presence of well dispersed CuO and ZnO phases in the calcined catalysts.
However, under reduction conditions, CuO was completely reduced to Cu particles
with an average size comprised between 34 and 42 nm. The catalytic activity shows
that the best yield of methanol was obtained with the CZA(51-22) at 250 C,
3.0 MPa and H2/CO2 = 3, which is due to the highest copper metallic surface area
and the interaction between copper and zinc oxide.