Low pressure-drop CuO/CeO2/UiO-66 catalysts for H2 purification

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 499; p. 155853
• Main Authors: Moraes, Carlos W. Dos Santos, Bernabéu, P. Gómez, Villegas, Katia J. Gómez, Bas, E. Guillén, López, I. Martínez, Suárez, F.E. López, Quiñonero, A. Davó, Jiménez, D. Fairén, Castelló, D. Lozano, López, A. Bueno
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2024
• Subjects: CeO2 catalyst; CO oxidation; CO-PROX; H2 purification; Pressure drop; UiO-66; γ−Al2O3; CeO2 catalyst; γ−Al2O3; CO oxidation; Pressure drop; H2 purification; UiO-66; CO-PROX
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.155853

[Display omitted] •UiO66 produces very low-pressure drop in comparison to conventional supports.•UiO66 improves the catalytic performance of CuO/CeO2 for CO oxidation in H2 streams.•UiO66 improves catalytic performance due to the enhanced gas diffusion.•Reaction gases are able to flow through UiO66 without channel constrictions. Pressure drop is responsible of a great part of the energy cost in industry due the energy consumed by pumps driving a fluid through the installation, and heterogeneous catalysis industrial processes suffer from this pressure drop penalty. This study demonstrates that UiO-66 significantly improves the catalytic performance of the CuO/CeO2 active phase for preferential CO oxidation in H2 streams with regard to a conventional γ-Al2O3 carrier due to the particular porous and crystalline properties of MOF materials. A packed bed of UiO-66 produces very low-pressure drop in comparison to conventional catalytic carriers, such as γ-Al2O3 or beta zeolite, being 4 times lower for UiO-66 than for γ-Al2O3 under 2 L/min flow of N2, and this ratio increases and approaches ∞ for lower gas flow rates. This feature of UiO-66 not only decreases the energy required to pump gases through the catalytic bed, but also improves catalytic performance of UiO-66-supported catalysts due to the enhanced gas diffusion into the catalytic bed. The reaction gases flow through the interparticle space left by the catalyst in a packed bed of CuO/CeO2/γ-Al2O3, and this produces high pressure drop, preferential gas pathways and mass transport limitations, negatively affecting the reaction rate. On the contrary, the reaction gases are able to flow through the UiO-66 material without channel constrictions, and the CuO/CeO2/UiO-66 catalysts avoid the gas diffusion restrictions of conventional catalysts.