Enhanced Catalytic Performance of Zr Modified CuO/ZnO/Al₂O₃ Catalyst for Methanol and DME Synthesis via CO₂ Hydrogenation
Zirconium (Zr) modified CuO/ZnO/Al2O3 (CZA) catalysts with different aluminum (Al) and Zr contents were synthesized by the co-precipitation method. The synthesized CuO/ZnO/ZrO2/Al2O3 (CZZA) catalysts were comprehensively characterized and studied for methanol synthesis via CO2 hydrogenation. The CZZA catalyst showed the highest methanol yield of 12.4 % at 220 °C and 2.76 MPa with an optimized catalyst composition of Cu/Zn/Zr/Al (atomic ratio) at 4:2:1:0.5. The CZZA catalyst showed better activity than that of the CZA catalyst and a superior stability for methanol synthesis. There was no decrease in the BET surface area and very little coke formation for the spent CZZA catalyst, after 300 h of methanol synthesis. Bifunctional catalysts, composed of CZZA and HZSM-5, were investigated for dimethyl ether (DME) synthesis directly from CO2 hydrogenation, and a maximum DME yield of 18.3 % was obtained at a reaction temperature of 240 °C and a pressure of 2.76 MPa. The stability of the bifunctional CZZA and HZSM-5 catalyst during the DME synthesis also significantly improved, as compared to that of the CZA and HZSM-5. A significant decrease in the BET surface area and an increase in coking on the spent CZZA catalyst were observed after 100 h of DME synthesis, indicating a detrimental effect on CZZA stability when a HZSM-5 catalyst was present. The changes in structural properties (e.g., BET surface area and crystallinity) and coking for HZSM-5 could be responsible for the deactivation of the bifunctional catalyst.
S. Ren and X. Fan and Z. Shang and W. R. Shoemaker and L. Ma and T. Wu and S. Li and N. B. Klinghoffer and M. Yu and X. Liang, "Enhanced Catalytic Performance of Zr Modified CuO/ZnO/Al₂O₃ Catalyst for Methanol and DME Synthesis via CO₂ Hydrogenation," Journal of CO2 Utilization, vol. 36, pp. 82-95, Elsevier, Feb 2020.
The definitive version is available at https://doi.org/10.1016/j.jcou.2019.11.013
Chemical and Biochemical Engineering
Keywords and Phrases
CO2hydrogenation; CuO/ZnO/ZrO2/Al2O3 (CZZA); Dimethyl ether; Methanol; Stability
International Standard Serial Number (ISSN)
Article - Journal
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