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. 2021 Jul 28;7(7):e07682.
doi: 10.1016/j.heliyon.2021.e07682. eCollection 2021 Jul.

Comparative study on the effect of different copper loading on catalytic behaviors and activity of Cu/ZnO/Al2O3 catalysts toward CO and CO2 hydrogenation

Tanutporn Kamsuwan  1 , Chadaporn Krutpijit  1 , Supareak Praserthdam  1 , Suphot Phatanasri  1 , Bunjerd Jongsomjit  1 , Piyasan Praserthdam  1
Affiliations

Comparative study on the effect of different copper loading on catalytic behaviors and activity of Cu/ZnO/Al2O3 catalysts toward CO and CO2 hydrogenation

Tanutporn Kamsuwan et al. Heliyon. .

Abstract

The ternary Cu/ZnO/Al2O3 (CZA) catalysts having different Cu loading were prepared by the co-precipitation method. Then, they were used in CO and CO2 hydrogenation to produce methanol under atmospheric pressure at 250 °C. The high Cu loading CZA catalyst (CZA-H) resulted in the enhancement of structural features and textural properties (e.g., BET surface area and the crystallite size of copper species). Furthermore, the conversion of CO and CO2 over CZA-H catalyst was apparently higher than that of the CZA-L (low Cu loading) catalyst. The major product of CO hydrogenation obtained from both catalysts was methanol, whereas in CO2 hydrogenation, the main product was CO. Deactivation of catalysts was also crucial during CO and CO2 hydrogenation. Therefore, the spent catalysts were determined to identify the nature of carbon formation. It revealed that amorphous and graphitic cokes were present. These cokes have different mechanisms in the elimination from the surface leading to influencing the deactivation process. The spent CZA-L was found to have higher carbon content, which was around 2.3% and 3.1% for CO and CO2 hydrogenation, respectively. Besides the amorphous coke, the graphitic coke was also observed in CZA-L after time on stream for 5 h.

Keywords: CO; CO2; Cu loading amount; Cu/ZnO/Al2O3 (CZA); Hydrogenation; Methanol production.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
XRD patterns of CZA-L (Cu/Zn = 0.8) and CZA-H (Cu/Zn = 3.0) catalysts.
Figure 2
Figure 2
SEM image of CZA-L and CZA-H catalysts.
Figure 3
Figure 3
XPS signals of CZA-L and CZA-H catalysts (a) XPS of Cu species, (b) XPS of Zn species and (c) XPS of Al species.
Figure 4
Figure 4
H2-TPR profile of CZA-L and CZA-H catalysts.
Figure 5
Figure 5
CO2-TPD profile of CZA-L and CZA-H catalysts.
Figure 6
Figure 6
Catalytic activity of CZA-L and CZA-H at different feedstocks at 250 °C under atmospheric pressure. (a) CO hydrogenation and (b) CO2 hydrogenation.
Figure 7
Figure 7
Proposed mechanism for the CO and CO2 hydrogenation over Cu-based catalyst.
Figure 8
Figure 8
TGA analysis of spent catalysts: (a) spent CZA-L and CZA-H catalysts after being used for 5 h in CO hydrogenation and (b) spent CZA-L and CZA-H catalysts after being used for 5 h in CO2 hydrogenation.
Figure 9
Figure 9
SEM images of spent CO-CZA-L, CO-CZA-H, CO2-CZA-L and CO2-CZA-H catalysts.
See this image and copyright information in PMC

References

    1. Ahmad R., Hellinger M., Buchholz M. Flame-made Cu/ZnO/Al2O3 catalyst for dimethyl ether production. Catal. Commun. 2014;43:52–56.
    1. Allam D., Cheknoun S., Hocine S. Operating conditions and composition effect on the hydrogenation of carbon dioxide performed over CuO/ZnO/Al2O3 catalysts. Bull. Chem. React. Eng. Catal. 2019;14(3):604–613.
    1. An X., Li J., Zuo Y. A Cu/Zn/Al/Zr fibrous catalyst that is an improved CO2 hydrogenation to methanol catalyst. Catal. Lett. 2007;118(3):264–269.
    1. Argyle M.D., Bartholomew C.H. Heterogeneous catalyst deactivation and regeneration: a review. Catalysts. 2015;5(1)
    1. Behrens M., Brennecke D., Girgsdies F. Understanding the complexity of a catalyst synthesis: Co-precipitation of mixed Cu,Zn,Al hydroxycarbonate precursors for Cu/ZnO/Al2O3 catalysts investigated by titration experiments. Appl. Catal. Gen. 2011;392(1):93–102.

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