Background: Microreactor devices have attracted increasing attention over the last years
due to their high surface-to-volume ratio, which ensures a high heat and mass transfer, short molecular
diffusion distance and greater spatial illumination homogeneity compared to the traditional reactors.
Objective: The aim of this study was to model the kinetics of photo-degradation of 2-propanol over
TiO2-based thin films in a gas-phase batch-reactor and simulate their performance in a microreactor
Methods: The reaction was carried out in a gas-phase batch-reactor, assessing the reactivity of singlelayer
nitrogen (N)-doped TiO2 and a bilayer consisting of N-doped TiO2 as a bottom layer and copper
(Cu)-doped TiO2 as a top layer. The kinetics of the photocatalytic process was modelled by Langmuir–
Hinshelwood (LH) model. The constants obtained from the LH model were used to simulate the
performance of the photocatalysts in a microreactor, operating in a continuous flow mode and investigating
the effect of the volumetric flow rate (Q), initial concentration of pollutant (Co), number of microchannels
(n) and microchannel length (l) on the photo-degradation of 2-propanol.
Results: N-Cu-TiO2 exhibited a higher reactivity but a lower adsorption ability towards the target pollutant
compared to N-TiO2. To maximize and leverage the advantages of a microreactor, optimal operating
conditions for a continuous flow mode, at a steady-state, should be moderately low Q and Co,
long l and n that minimizes flow maldistribution in parallel.
Conclusion: The findings in this work could serve as a basis to design and fabricate efficient microreactors
for the removal of VOC in air purification applications.