20.500.12556/DKUM-97667 Immobilized CuCl2/TiO2 photocatalysts for the selective oxidation of benzyl alcohol to benzaldehyde The oxidation of alcohols to aldehydes is a key transformation in industrial chemistry, as aldehydes are vital intermediates in the synthesis of pharmaceuticals and fine chemicals. Conventional oxidation routes typically employ stoichiometric and corrosive oxidants, generating significant environmental concerns. Greener oxidants such as molecular oxygen (O2) offer a more sustainable alternative to stoichiometric oxidants; however, their efficient utilization requires activation by catalysts (e.g., Cu-, Pd-, Au-, or Ti-based systems). Homogeneous photocatalysts such as CuCl2 exhibit promising activity under light irradiation but are limited by challenges in separation and recycling. This study investigates the immobilization of CuCl2 and TiO2 (P25) within sodium alginate beads to facilitate photocatalyst recovery and minimize metal leaching. Under UV irradiation for 4 h, benzyl alcohol conversions of 54% (P25) and 49% (CuCl2) were achieved. Catalyst encapsulation markedly reduced activity due to internal mass transport limitations, as restricted diffusion of O2 and benzyl alcohol within the bead matrix limited access to active sites and suppressed overall reaction rates. Co-immobilization of P25 and CuCl2 partially restored conversion (22%), while maintaining high benzaldehyde selectivity (≈1 after 4 h) across all systems. These findings highlight oxygen depletion and mass transfer resistance as key constraints in bead-based photocatalysts. To guide further optimization, a MATLAB-based reactor model incorporating species transport, interfacial mass transfer, and kinetics was developed. true false true Wiley Angleški jezik Angleški jezik https://onlinelibrary.wiley.com/journal/17511097 © 2026 The Author(s) Članek v reviji 2026-03-31 07:28:51 2026-03-31 07:28:51 2026-04-01 03:10:51 0000-00-00 00:00:00 2026 0 0 14 str. First published: 27 January 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2025-05-15 2025-12-13 2026-01-27 66.02 273130243 10.1111/php.70072 1751-1097 Photochem___Photobiology_-_2026_-_Nosrati‐Ghods_-_Immobilized_CuCl2_TiO2_photocatalysts_for_the_selective_oxidation_of.pdf Photochem___Photobiology_-_2026_-_Nosrati‐Ghods_-_Immobilized_CuCl2_TiO2_photocatalysts_for_the_selective_oxidation_of.pdf 1 2C0B1B9B1D73DD6891B2A32A0492E802 5ef6ea9bdd9f5e628aa161c243f5f19130e1ed49960e532e9bc878b4d0281f9e 85d100cf-2cc3-11f1-b3ef-00155d0001a1 https://dk.um.si/Dokument.php?lang=slv&id=204914 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0