Insight into the effects of confined hydrocarbon species on the lifetime of methanol conversion catalysts

Abstract

The methanol-to-hydrocarbons reaction refers collectively to a series of important industrial catalytic processes to produce either olefins or gasoline. Mechanistically, methanol conversion proceeds through a ‘pool’ of hydrocarbon species. For the methanol-to-olefins process, these species can be delineated broadly into ‘desired’ lighter olefins and ‘undesired’ heavier fractions that cause deactivation in a matter of hours. The crux in further catalyst optimization is the ability to follow the formation of carbonaceous species during operation. Here, we report the combined results of an operando Kerr-gated Raman spectroscopic study with state-of-the-art operando molecular simulations, which allowed us to follow the formation of hydrocarbon species at various stages of methanol conversion. Polyenes are identified as crucial intermediates towards formation of polycyclic aromatic hydrocarbons, with their fate determined largely by the zeolite topology. Notably, we provide the missing link between active and deactivating species, which allows us to propose potential design rules for future-generation catalysts.

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Fig. 1: Different stages of the MTO reaction and the Kerr-gate Raman spectroscopy set-up.
Fig. 2: Operando Kerr-gated Raman spectroscopy of SSZ-13 zeolite during the MTO reaction; formation of hydrocarbon pool intermediates and onset of deactivation.
Fig. 3: Comparison of experimental and simulated Raman spectra.
Fig. 4: Mobility of polyene species that are formed at the onset of deactivation.
Fig. 5: Operando Kerr-gated Raman spectroscopy of SSZ-13 zeolite during the MTO reaction; formation of PAHs and comparison with ZSM-5 and SAPO-34 archetypal MTH catalysts.
Fig. 6: Hydrocarbon species evolution during the MTO reaction on small-pore catalyst materials.

Data availability

Source data are provided with this paper. Example CP2K input files and processing scripts are available from the public GitHub online repository at https://github.com/AlexanderHoffman/supporting-info. Owing to the large size of the molecular dynamics trajectories and CP2K output files, they are available upon author request instead.

References

  1. 1.

    Olsbye, U. et al. Conversion of methanol to hydrocarbons: how zeolite cavity and pore size controls product selectivity. Angew. Chem. Int. Ed. 51, 5810–5831 (2012).

    CAS  Google Scholar 

  2. 2.

    Yarulina, I., Chowdhury, A. D., Meirer, F., Weckhuysen, B. M. & Gascon, J. Recent trends and fundamental insights in the methanol-to-hydrocarbons process. Nat. Catal. 1, 398–411 (2018).

    CAS  Google Scholar 

  3. 3.

    Yarulina, I. et al. Structure–performance descriptors and the role of Lewis acidity in the methanol-to-propylene process. Nat. Chem. 10, 804–812 (2018).

    CAS  Google Scholar 

  4. 4.

    Olsbye, U. et al. The formation and degradation of active species during methanol conversion over protonated zeotype catalysts. Chem. Soc. Rev. 44, 7155–7176 (2015).

    CAS  Google Scholar 

  5. 5.

    Hereijgers, B. P. C. et al. Product shape selectivity dominates the methanol-to-olefins (MTO) reaction over H-SAPO-34 catalysts. J. Catal. 264, 77–87 (2009).

    CAS  Google Scholar 

  6. 6.

    Bleken, F. et al. The effect of acid strength on the conversion of methanol to olefins over acidic microporous catalysts with the CHA topology. Top. Catal. 52, 218–228 (2009).

    CAS  Google Scholar 

  7. 7.

    Dahl, I. M. & Kolboe, S. On the reaction mechanism for hydrocarbon formation from methanol over SAPO-34: I. Isotopic labeling studies of the co-reaction of ethene and methanol. J. Catal. 149, 458–464 (1994).

    CAS  Google Scholar 

  8. 8.

    Dahl, I. M. & Kolboe, S. On the reaction mechanism for hydrocarbon formation from methanol over SAPO-34: 2. Isotopic labeling studies of the co-reaction of propene and methanol. J. Catal. 161, 304–309 (1996).

    CAS  Google Scholar 

  9. 9.

    Bjørgen, M. et al. Spectroscopic evidence for a persistent benzenium cation in zeolite H-beta. J. Am. Chem. Soc. 125, 15863–15868 (2003).

    Google Scholar 

  10. 10.

    McCann, D. M. et al. A complete catalytic cycle for supramolecular methanol‐to‐olefins conversion by linking theory with experiment. Angew. Chem. Int. Ed. 47, 5179–5182 (2008).

    CAS  Google Scholar 

  11. 11.

    Fu, H., Song, W. & Haw, J. F. Polycyclic aromatics formation in HSAPO-34 during methanol-to-olefin catalysis: ex situ characterization after cryogenic grinding. Catal. Lett. 76, 89–94 (2001).

    CAS  Google Scholar 

  12. 12.

    Li, C. et al. Synthesis of reaction‐adapted zeolites as methanol-to-olefins catalysts with mimics of reaction intermediates as organic structure‐directing agents. Nat. Catal. 1, 547–554 (2018).

    CAS  Google Scholar 

  13. 13.

    Arora, S. S., Nieskens, D. L. S., Malek, A. & Bhan, A. Lifetime improvement in methanol-to-olefins catalysis over chabazite materials by high-pressure H2 co-feeds. Nat. Catal. 1, 666–672 (2018).

    CAS  Google Scholar 

  14. 14.

    Hunger, M., Seiler, M. & Buchholz, A. In situ MAS NMR spectroscopic investigation of the conversion of methanol to olefins on silicoaluminophosphates SAPO-34 and SAPO-18 under continuous flow conditions. Catal. Lett. 74, 61–68 (2001).

    CAS  Google Scholar 

  15. 15.

    Wang, W., Buchholz, A., Seiler, M. & Hunger, M. Evidence for an initiation of the methanol-to-olefin process by reactive surface methoxy groups on acidic zeolite catalysts. J. Am. Chem. Soc. 125, 15260–15267 (2003).

    CAS  Google Scholar 

  16. 16.

    Dai, W. et al. Understanding the early stages of the methanol-to-olefin conversion on H-SAPO-34. ACS Catal. 5, 317–326 (2015).

    CAS  Google Scholar 

  17. 17.

    Wang, C. et al. Experimental evidence on the formation of ethene through carbocations in methanol conversion over H-ZSM-5 zeolite. Chem. Eur. J. 21, 12061–12068 (2015).

    CAS  Google Scholar 

  18. 18.

    Chua, Y. T. & Stair, P. C. An ultraviolet Raman spectroscopic study of coke formation in methanol to hydrocarbons conversion over zeolite H-MFI. J. Catal. 213, 39–46 (2003).

    CAS  Google Scholar 

  19. 19.

    Beato, P., Schachtl, E., Barbera, K., Bonino, F. & Bordiga, S. Operando Raman spectroscopy applying novel fluidized bed micro-reactor technology. Catal. Today 205, 128–133 (2013).

    CAS  Google Scholar 

  20. 20.

    Signorile, M. et al. Topology-dependent hydrocarbon transformations in the methanol-to-hydrocarbons reaction studied by operando UV-Raman spectroscopy. Phys. Chem. Chem. Phys. 20, 26580–26590 (2018).

    CAS  Google Scholar 

  21. 21.

    Howe, R. F. et al. Reactions of dimethylether in single crystals of the silicoaluminophosphate STA-7 studied via operando synchrotron infrared microspectroscopy. Top. Catal. 61, 199–212 (2018).

    CAS  Google Scholar 

  22. 22.

    Qian, Q. et al. Combined operando UV/Vis/IR spectroscopy reveals the role of methoxy and aromatic species during the methanol-to-olefins reaction over H-SAPO-34. ChemCatChem. 6, 3396–3408 (2014).

    CAS  Google Scholar 

  23. 23.

    Borodina, E. et al. Influence of the reaction temperature on the nature of the active and deactivating species during methanol to olefins conversion over H-SSZ-13. ACS Catal. 5, 992–1003 (2015).

    CAS  Google Scholar 

  24. 24.

    Goetze, J. et al. Insights into the activity and deactivation of the methanol-to-olefins process over different small-pore zeolites as studied with operando UV–vis spectroscopy. ACS Catal. 7, 4033–4046 (2017).

    CAS  Google Scholar 

  25. 25.

    Lesthaeghe, D., Horré, A., Waroquier, M., Marin, G. B. & Van Speybroeck, V. Theoretical insights on methylbenzene side-chain growth in ZSM-5 zeolites for methanol-to-olefin conversion. Chem. Eur. J. 15, 10803–10808 (2009).

    CAS  Google Scholar 

  26. 26.

    Forester, T. R. & Howe, R. F. In situ FTIR studies of methanol and dimethyl ether in ZSM-5. J. Am. Chem. Soc. 109, 5076–5082 (1987).

    CAS  Google Scholar 

  27. 27.

    Stair, P. C. The application of UV Raman spectroscopy for the characterization of catalysts and catalytic reactions. Adv. Catal. 51, 75–98 (2007).

    CAS  Google Scholar 

  28. 28.

    Kim, H., Kosuda, K. M., Van Duyne, R. P. & Stair, P. C. Resonance Raman and surface- and tip-enhanced Raman spectroscopy methods to study solid catalysts and heterogeneous catalytic reactions. Chem. Soc. Rev. 39, 4820–4844 (2010).

    CAS  Google Scholar 

  29. 29.

    Matousek, P., Towrie, M., Stanley, A. & Parker, A. W. Efficient rejection of fluorescence from Raman spectra using picosecond Kerr gating. Appl. Spectrosc. 53, 1485–1489 (1999).

    CAS  Google Scholar 

  30. 30.

    Matousek, P., Towrie, M. & Parker, A. W. Fluorescence background suppression in Raman spectroscopy using combined Kerr gated and shifted excitation Raman difference techniques. J. Raman Spectrosc. 33, 238–242 (2002).

    CAS  Google Scholar 

  31. 31.

    Blaszkowski, S. R. & van Santen, R. A. The mechanism of dimethyl ether formation from methanol catalyzed by zeolitic protons. J. Am. Chem. Soc. 118, 5152–5253 (1996).

    CAS  Google Scholar 

  32. 32.

    Allotta, P. M. & Stair, P. C. Time-resolved studies of ethylene and propylene reactions in zeolite H-MFI by in-situ fast IR heating and UV Raman spectroscopy. ACS Catal. 2, 2424–2432 (2012).

    CAS  Google Scholar 

  33. 33.

    Socrates, G. Infrared and Raman Characteristic Group Frequencies 3rd edn (Wiley, 2004).

  34. 34.

    Ghysels, A. et al. Shape-selective diffusion of olefins in 8-ring solid acid microporous zeolites. J. Phys. Chem. C 119, 23721–23734 (2015).

    CAS  Google Scholar 

  35. 35.

    Tinnemans, S. J., Kox, M. H. F., Nijhuis, T. A., Visser, T. & Weckhuysen, B. M. Real time quantitative Raman spectroscopy of supported metal oxide catalysts without the need of an internal standard. Phys. Chem. Chem. Phys. 7, 211–216 (2005).

    CAS  Google Scholar 

  36. 36.

    Bjørgen, M. et al. Conversion of methanol to hydrocarbons over zeolite H-ZSM-5: on the origin of the olefinic species. J. Catal. 249, 195–207 (2007).

    Google Scholar 

  37. 37.

    Database of Zeolite Structures http://www.iza-structure.org/databases (2017).

  38. 38.

    Mores, D. et al. Space- and time-resolved in-situ spectroscopy on the coke formation in molecular sieves: methanol-to-olefin conversion over H-ZSM-5 and H-SAPO-34. Chem. Eur. J. 14, 11320–11327 (2008).

    CAS  Google Scholar 

  39. 39.

    Borodina, E. et al. Influence of the reaction temperature on the nature of the active and deactivating species during methanol-to-olefins conversion over H-SAPO-34. ACS Catal. 7, 5268–5281 (2017).

    CAS  Google Scholar 

  40. 40.

    Hwang, A., Kumar, M., Rimer, J. D. & Bhan, A. Implications of methanol disproportionation on catalyst lifetime for methanol-to-olefins conversion by HSSZ-13. J. Catal. 346, 154–160 (2017).

    CAS  Google Scholar 

  41. 41.

    Li, Y., Yu, J. & Xu, R. Criteria for zeolite frameworks realizable for target synthesis. Angew. Chem. Int. Ed. 52, 1673–1677 (2013).

    CAS  Google Scholar 

  42. 42.

    Li, Y. & Yu, J. New stories of zeolite structures: their descriptions, determinations, predictions, and evaluations. Chem. Rev. 114, 7268–7316 (2014).

    CAS  Google Scholar 

  43. 43.

    Moliner, M., Franch, C., Palomares, E., Grill, M. & Corma, A. Cu–SSZ-39, an active and hydrothermally stable catalyst for the selective catalytic reduction of NOx. Chem. Commun. 48, 8264–8266 (2012).

    CAS  Google Scholar 

  44. 44.

    Lezcano-Gonzalez, I. et al. Determining the storage, availability and reactivity of NH3 within Cu–chabazite-based ammonia selective catalytic reduction systems. Phys. Chem. Chem. Phys. 16, 1639–1650 (2014).

    CAS  Google Scholar 

  45. 45.

    Hutter, J., Iannuzzi, M., Schiffmann, F. & VandeVondele, J. CP2K: atomistic simulations of condensed matter systems. Wiley Interdiscip. Rev. Comput. Mol. Sci. 4, 15–25 (2014).

    CAS  Google Scholar 

  46. 46.

    Lippert, G., Hutter, J. & Parrinello, M. The Gaussian and augmented-plane-wave density functional method for ab initio molecular dynamics simulations. Theor. Chem. Acc. 103, 124–140 (1999).

    CAS  Google Scholar 

  47. 47.

    Yang, K., Zheng, J., Zhao, Y. & Truhlar, D. G. Tests of the RPBE, revPBE, τ-HCTHhyb, ωB97X-D, and MOHLYP density functional approximations and 29 others against representative databases for diverse bond energies and barrier heights in catalysis. J. Chem. Phys. 132, 164117 (2010).

    Google Scholar 

  48. 48.

    Goedecker, S., Teter, M. & Hutter, J. Separable dual-space Gaussian pseudopotentials. Phys. Rev. B 54, 1703–1710 (1996).

    CAS  Google Scholar 

  49. 49.

    Cnudde, P. et al. How chain length and branching influence the alkene cracking reactivity on H-ZSM-5. ACS Catal. 8, 9579–9595 (2018).

    CAS  Google Scholar 

  50. 50.

    Frenkel, D. & Smit, B. Understanding Molecular Simulation 2nd edn (Academic Press, 2002).

  51. 51.

    Luber, S., Iannuzzi, M. & Hutter, J. Raman spectra from ab initio molecular dynamics and its application to liquid S-methyloxirane. J. Chem. Phys. 141, 094503 (2014).

    Google Scholar 

  52. 52.

    Thomas, M., Brehm, M., Fligg, R., Vöhringer, P. & Kirchner, B. Computing vibrational spectra from ab initio molecular dynamics. Phys. Chem. Chem. Phys. 15, 6608–6622 (2013).

    CAS  Google Scholar 

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Acknowledgements

This research has been performed with the use of facilities including a Raman spectrometer and thermogravimetric analysis equipment at the Research Complex at Harwell. We thank the Research Complex for access and support to these facilities and equipment. We acknowledge the Engineering and Physical Sciences Research Council for funding grants EP/K007467/1, EP/K014706/2, EP/K014668/1, EP/K014854/1, EP/K014714/1, EP/M013219/1, EP/S016481/1 and EP/S016481/1. The Science and Technology Facilities Council (STFC) is acknowledged for the beam time at the ULTRA facility for performing Kerr-gate experiments. L. Mantarosie (Johnson Matthey PLC) is also thanked for her assistance and expertise. P. Matousek and T. Parker (STFC) are acknowledged for useful discussions. V.V.S., A.E.J.H. and M.B. acknowledge the Research Foundation – Flanders (FWO), the Special Research Fund of Ghent University, and funding from the Horizon 2020 research and innovation program of the European Union (consolidator European Research Council grant agreement no. 647755 – DYNPOR (2015–2020)). The computational resources and services were provided by Ghent University (Stevin Supercomputer Infrastructure) and the Flemish Supercomputer Center, and funded by the FWO.

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Contributions

I.L.-G. and A.M.B. conceived and coordinated the project with V.V.S., M.T. and I.V.S. as close collaborators. I.L.-G. performed the operando Kerr-gated Raman experiments, and E.C., M.A.-A., E.K.G., A.G. and I.V.S. supported the work. A.E.J.H., M.B., K.d.W. and V.V.S. performed the molecular simulations. I.L.-G., E.C., A.E.J.H., V.V.S., K.d.W., A.M.B., M.T. and I.V.S. contributed to the data analysis and discussion. I.L.-G., E.C., A.E.J.H., V.V.S. and A.M.B. wrote the manuscript with input from all authors.

Corresponding authors

Correspondence to I. Lezcano-Gonzalez or V. Van Speybroeck or A. M. Beale.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–43, Tables 1–2 and Refs. 1–44.

Source data

Source Data Fig. 2

Processed Kerr-gated Raman data recorded during the MTH reaction between 250 and 300 °C on SSZ-13 zeolite; processed mass spectrometry data recorded during the MTH reaction between 240 and 310 °C on SSZ-13 zeolite.

Source Data Fig. 3

Comparison between processed Kerr-gated Raman data recorded during the MTH reaction at 260, 280 and 300 °C and the simulated spectra of propene, isoprene, butadiene, trimethylnaphthalene, trimethylbenzene, dimethylpentadiene and heptatriene.

Source Data Fig. 4

Position of the centre of mass of the carbon atoms projected on one of the 8-ring channels and a direction perpendicular to it for the intermediates propene, heptatriene and decapentaene.

Source Data Fig. 5

Processed Kerr-gated Raman data recorded during the MTH reaction between 320 and 450 °C on SSZ-13 zeolite; simulated Raman spectra of anthracene and anthracene precursor; processed Kerr-gated Raman data recorded after quenching the MTH reaction at 450 °C in SSZ-13, ZSM-5 and SAPO-34 catalyst materials.

Source Data Fig. S3

Processed Kerr-gated Raman data recorded before and after methanol adsorption at 100 °C on SSZ-13 zeolite.

Source Data Fig. S4

Processed Kerr-gated Raman data recorded during the MTH reaction between 100 and 240 °C on SSZ-13 zeolite; processed mass spectrometry data recorded during the MTH reaction between 100 and 250 °C on SSZ-13 zeolite.

Source Data Fig. S38

Processed Kerr-gated Raman data recorded during the MTH reaction on SSZ-13 zeolite under isothermal conditions at 280 and 350 °C; processed mass spectrometry data recorded during the MTH reaction on SSZ-13 zeolite under isothermal conditions at 280 and 350 °C.

Source Data Fig. S39

Processed Kerr-gated Raman data recorded during the MTH reaction between 280 and 340 °C on ZSM-5 zeolite; processed mass spectrometry data recorded during the MTH reaction between 260 and 350 °C on ZSM-5 zeolite; processed Kerr-gated Raman data recorded during the MTH reaction between 360 and 450 °C on ZSM-5 zeolite.

Source Data Fig. S40

Processed Kerr-gated Raman data recorded during the MTH reaction between 210 and 450 °C on SAPO-34; processed mass spectrometry data recorded during the MTH reaction between 250 and 350 °C on SAPO-34.

Source Data Fig. S41

Processed Raman data recorded using a lab-based Raman spectrometer (830 nm) for SSZ-13 zeolite after the MTH reaction at 450 °C and for Mo/H-ZSM-5 zeolite after methane dehydroaromatization at 700 °C for 30 h (GHSV 1500 h−1).

Source Data Fig. S42

Thermogravimetric analysis of SSZ-13 zeolite after the MTH reaction at 450 °C.

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Lezcano-Gonzalez, I., Campbell, E., Hoffman, A.E.J. et al. Insight into the effects of confined hydrocarbon species on the lifetime of methanol conversion catalysts. Nat. Mater. 19, 1081–1087 (2020). https://doi.org/10.1038/s41563-020-0800-y

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