A Hybrid Photocatalytic-Electrostatic Reactor for Nitrogen Oxides Removal
A combined photocatalytic-electrostatic apparatus for the removal of indoor levels of nitrogen oxides (NOx) has been evaluated. Titanium Dioxide (TiO2) photocatalysis has been reported as inexpensive promising method to reduce gaseous environmental pollutants while electrostatic precipitation (ESP) is a highly efficient process for removing fine particles through the action of an induced electrostatic field. This article is aimed to study the synergic effect of the two processes combined into one reactor. In particular it has been studied: (i) the efficiency of NO removal and the selectivity for nitrogen dioxide (NO2), (ii) their dependence from the plate-wire configuration and the inlet mass flow, (iii) the generation of ozone by ESP and its reduction by the photo activated TiO2, (iv) the photo inhibitory effect on TiO2 by adsorbed nitrates. A simplified path flow reaction will be also presented.
TiO2 Catalysis, ESP, NOx, Nitrates Inhibition, Ozone Reduction
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