Towards High CO2 Conversions Using Cu/Zn Catalysts Supported on Aluminum Fumarate Metal-Organic Framework for Methanol Synthesis

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.

Effects of Particle Size on the Gas Uptake Kinetics and Physical Properties of Type III Porous Liquids

“…However, for all samples, a 20% weight loss under 100 °C was observed suggesting significant water was present due to rehydration on exposure to ambient air before the measurement. The decomposition temperatures are all between 450 and 500 °C which is consistent with literature . The crystallite sizes according to PXRD and the Scherrer equation were similar for all samples at 24 ± 2 nm.…”

“…The decomposition temperatures are all between 450 and 500 °C which is consistent with literature. 15 The crystallite sizes according to PXRD and the Scherrer equation were similar for all samples at 24 ± 2 nm. N 2 -Brunnauer−Emmett−Teller (N 2 -BET) adsorption and desorption measurements were obtained, and the derived surface areas and pore volumes are given in Table 1.…”

Direct Synthesis of Dimethyl Ether from CO2 Hydrogenation over Core-Shell Nanotube Bi-Functional Catalyst

“…The XRD patterns in (Figure 1a) for both HNT and DMF-HNT showed similar peaks at 2θ 210. 2, 11.8, 19.8, 24.8, 26.5, 34.8, 35.7, 38.1, 54.5, 62.3, 73.5, 77.13. Catalysts 2023, 13, 408 5 It can be seen that the crystallinity of the CuZnO decreases, which may be du low metal loading and good dispersion [42]. However, this interface between Cu ZnO species is proposed as the active site and shows promising results for the meth synthesis step [43].…”

MOF-based catalysts: insights into the chemical transformation of greenhouse and toxic gases

“…The number of active sites is doubled, the CO 2 conversion increases more than four times, and there is an improvement in the selectivity for methanol. 84…”

“…The number of active sites is doubled, the CO 2 conversion increases more than four times, and there is an improvement in the selectivity for methanol. 84 The transformation of CO 2 into cyclic carbonates is typically based on the opening of epoxides, which can be of different sizes, in the presence of Lewis or Brønsted acids. 85 The cyclic carbonates produced by this reaction are interesting to the pharmaceutical industry and are also used as a polar aprotic degreaser or solvent.…”