Pd/TiO2 doped faujasite photocatalysts for acetophenone transfer hydrogenation in a photocatalytic membrane reactor

Different titanium faujasite photocatalysts have been prepared and tested in the transfer hydrogenation of acetophenone to phenyl ethanol, an industrially relevant product. Water as solvent, formic acid as hydrogen and electron donor and UV and visible light irradiation, have been employed. The 10% loaded titanium faujasite prepared using propanol as solvent (TF10P) showed the best homogeneous dispersion of TiO2 particles on the zeolite surface, BET and pore volume values and photocatalytic performance. A further functionalization of the TF10P photocatalyst with Pd particles (Pd_TF10P), shifted the catalytic response in the visible range. The productivity, normalized by the light intensity, obtained by using the Pd_TF10P photocatalyst under visible light was a little lower than that obtained by using the TF10P under UV light (12.56 mg gTiO2 -1 h-1 cm2 W-1 vs 19.11 mg gTiO2 -1 h-1 cm2 W-1) but the advantage could be the use of direct solar ligth as energy source. The photocatalytic membrane reactor had an extraction percentage of phenylethanol from the reactive phase to the organic phase of ca. 25%. The results also evidenced the possibility to use the visible light in this photocatalytic system in the photocatalytic reduction of acetophenone.