Abstract:
Green methanol is a viable alternative for the storage of hydrogen and may be produced
from captured anthropogenic sources of carbon dioxide. The latter was hydrogenated over Cu-ZnO
catalysts supported on an aluminum fumarate metal-organic framework (AlFum MOF). The catalysts,
prepared via slurry phase impregnation, were assessed for thermocatalytic hydrogenation of CO2 to
methanol. PXRD, FTIR, and SBET exhibited a decrease in crystallinity of the AlFum MOF support
after impregnation with Cu-Zn active sites. SEM, SEM-EDS, and TEM revealed that the morphology
of the support is preserved after metal loading, where H2-TPR confirmed the presence of active
sites for hydrogen uptake. The catalysts exhibited good activity, with a doubling in Cu and Zn
loading over the AlFum MOF, resulting in a 4-fold increase in CO2 conversions from 10.8% to 45.6%
and an increase in methanol productivity from 34.4 to 56.5 gMeOH/Kgcat/h. The catalysts exhibited
comparatively high CO selectivity and high yields of H2O, thereby favoring the reverse water-gas
shift reaction. The selectivity of the catalysts towards methanol was found to be 12.9% and 6.9%. The
performance of the catalyst supported on AlFum MOF further highlights the potential use of MOFs
as supports in the heterogeneous thermocatalytic conversion of CO2 to value-added products.
Description:
SUPPLEMENTARY MATERIAL : FIGURE S1: Individual elemental maps of 7Cu/3Zn/AlFum MOF. (a) Al K 1; (b) Cu K 1; and (c) Zn K 1; FIGURE S2: Individual elemental maps of 15Cu/6.4Zn/AlFum MOF. (a) Al K 1; (b) Cu K 1; and (c) Zn K 1; FIGURE S3: Derivative TGA plot of AlFum MOF. FIGURE S4: Derivative TGA plot of 7Cu/3ZnO/AlFum MOF; FIGURE S5: Derivative TGA plot of 15Cu/6.4ZnO/AlFum MOF.
