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. 2024 Jan 19;10(3):eadk2081.
doi: 10.1126/sciadv.adk2081. Epub 2024 Jan 17.

Doubling the life of Cu/ZnO methanol synthesis catalysts via use of Si as a structural promoter to inhibit sintering

Nathan Barrow  1 , Jonathan Bradley  1 , Benjamin Corrie  2 , Youxin Cui  2 , Trung Dung Tran  1 , Tugce Eralp Erden  1 , Andrew Fish  2 , Monica Garcia  2 , Pauline Glen  2 , Neetisha Mistry  2 , Michael Nicholson  2 , Simone Roloff-Standring  2 , Daniel Sheldon  2 , Thomas Smith  2 , Aron Summer  1 , Kaamila Un Din  2 , Norman Macleod  2
Affiliations

Doubling the life of Cu/ZnO methanol synthesis catalysts via use of Si as a structural promoter to inhibit sintering

Nathan Barrow et al. Sci Adv. .

Abstract

Cu/ZnO/Al2O3 catalysts used to synthesize methanol undergo extensive deactivation during use, mainly due to sintering. Here, we report on formulations wherein deactivation has been substantially reduced by the targeted use of a small quantity of a Si-based promoter, resulting in accrued activity benefits that can exceed a factor of 1.8 versus unpromoted catalysts. This enhanced stability also provides longer lifetimes, up to double that of prior generation catalysts. Detailed characterization of a library of aged catalysts has allowed the most important deactivation mechanisms to be established and the chemical state of the silicon promoter to be identified. We show that silicon is incorporated within the ZnO lattice, providing a pronounced improvement in the hydrothermal stability of this component. These findings have important implications for sustainable methanol production from H2 and CO2.

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Figures

Fig. 1.
Fig. 1.. The impact of Si addition on activity retention with time online under a variety of conditions and at different scales.
All activities are quoted relative to a standard Si-free reference catalyst aged under the same conditions. (A) Accelerated aging, (B) Sidestream aging, (C) commercial reference charge, and (D) renewable methanol (H2 + CO2). In (B), □ represents the relative activity measured in a laboratory microreactor following the return of the Sidestream samples to JM’s laboratories.
Fig. 2.
Fig. 2.. Structural changes associated with deactivation.
Samples aged in the AAR unit to generate a range of residual activities (A/A0). (A) Relationship between copper surface area (N2O) and activity; (B) sintering of Cu and ZnO components as determined by XRD.
Fig. 3.
Fig. 3.. Simultaneous aging of Si-doped and Si-free samples in Berty reactor.
(A) Cu domain size (XRD) as a function of aging time; (B) ZnO domain size (XRD) as a function of aging time.
Fig. 4.
Fig. 4.. 29Si solid-state MAS NMR spectra of aged Si-doped catalysts (0.4 wt % SiO2).
Spectra obtained via both direct and 1H-29Si cross-polarization (CP).
Fig. 5.
Fig. 5.. ZnO domain sizes (XRD) as a function of Si:Zn molar ratio for model binary systems.
Domain sizes plotted both in the fresh (calcined) state and following a period of aging under accelerated conditions.
See this image and copyright information in PMC

References

    1. Laudenschleger D., Ruland H., Muhler M., Identifying the nature of the active sites in methanol synthesis over Cu/ZnO/Al2O3 catalysts. Nat. Commun. 11, 3898 (2020). - PMC - PubMed
    1. Kattel S., Ramirez P. J., Chen J. G., Rodriguez J. A., Liu P., Active sites for CO2hydrogenation to methanol on Cu/ZnO catalysts. Science 355, 1296–1299 (2017). - PubMed
    1. Frei E., Gaur A., Lichtenberg H., Zwiener L., Scherzer M., Girgsdies F., Lunkenbein T., Schlögl R., Cu−Zn alloy formation as unfavored state for efficient methanol catalysts. ChemCatChem 12, 4029–4033 (2020).
    1. Kuld S., Thorhauge M., Falsig H., Elkjær C. F., Helveg S., Chorkendorff I., Sehested J., Quantifying the promotion of Cu catalysts by ZnO for methanol synthesis. Science 352, 969–974 (2016). - PubMed
    1. Dalebout R., Barberis L., Totarella G., Turner S. J., La Fontaine C., de Groot F. M. F., Carrier X., van der Eerden A. M. J., Meirer F., de Jongh P. E., Insight into the nature of the ZnOx promoter during methanol synthesis. ACS Catal. 12, 6628–6639 (2022). - PMC - PubMed