Scaling Up of a Photoreactor for Formic Acid Degradation Employing Hydrogen Peroxide and UV Radiation

LABAS, M. D.; ZALAZAR, C. S.; BRANDI, R. J.; MARTÍN, C. A.; CASSANO, A. E.

HELVETICA CHIMICA ACTA

WILEY-V C H VERLAG GMBH

Año: 2002 p. 82 - 85

0018-019X

A model for scaling up a homogeneous photoreactor was developed and experimentally verified in a pilot-plant-size apparatus. The procedure is exemplifield by the oxidation of dilute aqueous HCOOH solutions with UV radiation (254nm) and H2O2. First , the kinetic parameters of the HCOOH degradation were obtained in a well-stirred, small, batch flat-plate photoreactor (volumen = 70ml). The method employed in the analysis of the analysis of the experimental results yielded reaction-rate expressions for HCOOH and H2O2 that were independent of the reactor configuration. These kinetic equation and the corresponding kinetic constants were then used in a mathematical, fully deterministic model of a continuous-flow.2-m-longitud, annular reactor (0.0065 m2 of cross section for flow) operating in a laminar-flow regime to predict exit concentrations of HCOOH. Irradiation was provided in both cases by two different types of germicidal lamps. No additional experiments were made to adjust the reactor-model parameters. Theoretical predictions from the representation of the reactor performance obtained were compared with experimental data furnished by experiments in the much-larger-size, cylindrical-flow reactor. Results showed good agreement for the range of variables explored; the correspondend to expected operating conditions in water streams polluted with low concentrations of organic compounds.