INVESTIGADORES
ALFANO Orlando Mario
congresos y reuniones científicas
Título:
Photocatalytic degradation of tetrachloroethylene in gas phase on TiO2 films: A kinetic study
Autor/es:
IMOBERDORF, G.E.; IRAZOQUI, H.A.; ALFANO, O.M.
Lugar:
Praga
Reunión:
Congreso; CHISA 2004. 16th International Congress on Chemical and Process Engineering; 2004
Resumen:
A number of volatile chlorinated organic compounds are used industrially as solvents in operations of dry cleaning and degreasing of metals. Among them, tetrachloroethylene or perchloroethylene (PCE) is a toxic and carcinogenic agent, highly persistent in the environment. Photocatalytic reactions using TiO2 as the catalyst are an effective means for its elimination. Photoreactors design requires knowing the mechanism and kinetics of the photocatatalytic reactions involved, including the steps describing the interaction of the radiation field with the catalytic surface. In this work, the degradation of PCE in an air stream was studied for different values of PCE feed concentrations, relative humidity levels and light intensities. The TiO2 photocatalyst was deposited as a thin film on a borosilicate glass plate by means of a sol-gel technique. The reactor was operated under kinetic control regime. An expression of the intrinsic reaction kinetics was developed. This expression is based on a model of the absorption of radiant energy on the surface of the catalyst, followed by a detailed reaction mechanism based on a reaction scheme that involves Cl· as an active reaction intermediate. Experimental results from a differential photoreactor were used to validate the proposed kinetic model and to determine the kinetic parameters by non-linear regression of experimental data.