Cu/Zn/Al/Zr catalysts via phase-pure hydrotalcite-like compounds for methanol synthesis from carbon dioxide.

Cu/Zn/Al/Zr catalysts with Cu 2+ :Zn 2+ :Al 3+ :Zr 4+ = 2:1: x :0.1 ( x = 0.6–1.5) were prepared from hydrotalcite-like precursors by co-precipitation method and tested for the CO 2 hydrogenation to methanol. Both Cu/Zn/Al/Zr hydrotalcite-like and malachite phase were formed at low Al content. However, with the increase of Al content, the yield of hydrotalcite-like phase increased and phase-pure Cu/Zn/Al/Zr hydrotalcite-like compound was obtained for x ≥ 0.9. In addition, both the specific surface area and the dispersion of Cu increased gradually with the increase of Al, while the exposed Cu surface area first increased until Al content was 27.9 mol%, then decreased. The results of catalytic test for CO 2 hydrogenation revealed that Cu/Zn/Al/Zr catalysts via phase-pure hydrotalcite-like compounds exhibited much better catalytic performance with higher CO 2 conversion and CH 3 OH selectivity compared with the catalyst derived from mixed phase (hydrotalcite-like and malachite). The Cu/Zn/Al/Zr catalysts with Cu 2+ :Zn 2+ :Al 3+ :Zr 4+ = 2:1:1.2:0.1 resulting from phase-pure hydrotalcite-like precursors afforded the substantial stability and the best catalytic performance. [ABSTRACT FROM AUTHOR]