Heterogeneous photocatalytic reduction of ferrate(VI) in UV-irradiated titania suspensions: Role in enhancing destruction of nitrogen-containing pollutants

Sharma, Virender K.; Winkelmann, Kurt; Krasnova, Yekaterina; Lee, Changyoul; Sohn, Mary

doi:https://doi.org/10.1155/S1110662X0300031X

Abstract

The results of the heterogeneous photocatalytic reduction of Fe(VI) in UV-irradiated TiO2 suspensions are presented and suggest indirect observation of the formation of Fe(V) by the photoreduction of Fe(VI) with ecb− at TiO2 surfaces. Because Fe(V) selectively and rapidly oxidizes low reactivity pollutants with the production of the non-toxic by-product, Fe(III), the photocatalytic reduction of Fe(VI) has a role in pollution remediation processes. The experiments were conducted as a function of TiO2 suspension concentrations, Fe(VI) concentrations, and pH in basic media. The initial rate of Fe(VI) reduction gave a fractional order with respect to initial Fe(VI) concentrations and adheres to simple Langmuir-Hinshelwood kinetics. Results suggest that the surface reaction (Fe(VI)+ecb−→Fe(V)) is the rate-controlling step. The photocatalytic reduction of Fe(VI) in the presence of less reactive nitrogen-containing species (ammonia, cyanate, and fulvic acid) were also investigated. Enhancement in the rate of Fe(VI) reduction was observed. A reaction scheme involving Fe(V) as an intermediate is presented which explains the faster photocatalytic oxidation of pollutants in the presence of Fe(VI).

Copyright

Copyright © 2003 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

International Journal of Photoenergy

Heterogeneous photocatalytic reduction of ferrate(VI) in UV-irradiated titania suspensions: Role in enhancing destruction of nitrogen-containing pollutants

Abstract

Copyright

More related articles