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To investigate the heterogeneity of the catalyst and the metal
leaching, the hydroxylation reaction of phenol was maintained
for 1 h in the presence of CuO@CeO2-800 ꢀC catalyst. Aer that,
the catalyst was ltered and the ltrate obtained is stirred for
additional 2 h at 80 ꢀC, the portion containing the catalyst
showed 22% of phenol conversion, while the catalyst-free portion
showed no product, evidently proving the heterogeneity of the
catalyst. Metal leaching was studied by ICP-AES analysis of the
catalyst before and aer the reaction. The copper concentration
of the catalyst was found to 4.6% for fresh catalyst and 4.4% aer
one catalytic cycle in phenol hydroxylation, which conrms
negligible copper leaching. The catalytic activity of CuO@CeO-
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4. Conclusion
In summary, in this work, the objective is to explore new routes
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`
`
´
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Acknowledgements
´
We thank MAScIR Foundation for funding and support. We 24 J. A. Rodriguez, S. Ma, P. Liu, J. Hrbek, J. Evans and M. Perez,
acknowledge also the nancial assistance of the CNRST.
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