In this study

a practical process for ozonization of benzyl alcohols to ketones and aldehydes in a rotating packed bed (RPB-O

3

) reactor has been developed. Using 1-phenylethanol as a model reactant

the performance of RPB-O

3

process in different solvents has been compared with the commonly used stirred tank reactor (STR-O

3

). Ethyl acetate was the optimum solvent for the conversion of 1-phenylenthanol to acetophenone in RPB-O

3

process

with 78% yield after 30 min. In a parallel STR-O

3

experiment

the yield of acetophenone was 50%. Other experimental variables

i.e

. O

3

concentration

reaction time

high-gravity factor and liquid flow rate were also optimized. The highest yield of acetophenone was obtained using O

3

concentration of 80 mg·L

-1

reaction time of 30 min

high gravity factor of 40 and liquid flow rate of 120 L·h

-1

. Under the optimized reaction conditions

a series of structurally diverse primary and secondary alcohols was oxidized with (19%-92%) yield. The ozonization mechanism was studied by Electron Paramagnetic Resonance (EPR) spectros

copy

monitoring the radical species formed upon self-decomposition of O

3

. The characteristic quadruple peak with the 1:2:2:1 intensity ratio that corresponds to hydroxyl radicals (·OH) was observed in the electron paramagnetic resonance (EPR) spectrum

indicating an indirect oxidation mechanism of alcohols

via

·OH radical.