Destruction of malodorous compounds using heterogeneous photocatalysis

Photocatalytic oxidation of the sulfur-containing compounds, trimethylene s ulfide (C3H6S), propylene sulfide (C3H6S), thiophene (C4H4S), and methyl di sulfide (C2H6S2), was carried out using an annular plug flow reactor with T iO2 in a supported form. Formation of products and byproducts was monitored in realtime using a mass spectrometry online system. Mineralization of the sulfur-containing compounds was confirmed by mass balance of CO2 and SO42- . Dilute contaminated atmospheres of trimethylene sulfide and propylene sul fide were completely mineralized. For thiophene and methyl disulfide, howev er, partial oxidation was observed, generating sulfur dioxide (SO2) and sul fur oxide (SO) as byproducts, which were confirmed by parent ion MS/MS spec tra as well as by chemical ionization. Sensory analysis showed that for tri methylene sulfide and propylene sulfide, odor intensity after TiO2/UV treat ment was below the olfactive threshold limit of the panel.