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RSC Advances
ethanol dehydrogenation for 6 h the catalysts were calcined at images and Prof. J. M. C. Bueno for the CO/DRIFTS adsorption
500 ꢁC followed by reduction at 250 ꢁC in H2. Aer regeneration, experiments.
the catalytic activity was not restored at all and the copper
particle size increased (Fig. 5 and Table 2). The increase in
particle size between 2–2.5 nm appears to favor to increase the
References
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increase of sintering of the copper particles of the catalysts
which increased ethyl acetate selectivity up to about 8%. The
sintering process is more evident in the non-porous Cu/AlMgO
(Fig. 5c). Finally, aer the thermal treatment at 500 ꢁC and
sintering of copper, the surface of the support led to the
occurrence of the dehydration on ethanol to ethene, with
a selectivity of about 5%.
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Acknowledgements
The authors gratefully acknowledge the nancial support 22 R. A. Hoyt, M. M. Montemore, E. C. H. Sykes and E. Kaxiras,
˜
provided by the Sao Paulo State Research Foundation (FAPESP,
grant numbers #2013/01328-0 and #2015/05321-5) and CNPq 23 J. Quesada, L. Faba, E. Dıaz and S. Ordonez, ChemCatChem,
(grant number #306326/2017-5). The authors also acknowledge 2018, 10, 3583–3592.
the XAFS1 beamline of the Brazilian Synchrotron Light Labo- 24 M. Ohira, H. Liu, D. He, Y. Hirata, M. Sano, T. Suzuki and
J. Phys. Chem. C, 2018, 122, 21952–21962.
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ratory (LNLS) for the XAS measurements, LCE-UFSCar for SEM
T. Miyake, J. Jpn. Pet. Inst., 2018, 61, 205–212.
This journal is © The Royal Society of Chemistry 2019
RSC Adv., 2019, 9, 3294–3302 | 3301