Photocatalytic oxidation of toxic organohalides with TiO"2/UV: The effects of humic substances and organic mixtures [An article from: Chemosphere]

This digital document is a journal article from Chemosphere, published by Elsevier in 2007. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
TiO"2/UV photocatalytic oxidation of DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane), 1,2,3-trichlorobenzene and 4-chlorophenol were examined in aqueous solution in the presence of humic substances and organic mixtures to study if the degradation rates were affected. Both commercial and natural humic substances were observed to retard the photodegradation rates, with a greater effect from the natural humic substances. Acetonitrile and isopropanol also caused significant retardation of 4-chlorophenol photodegradation. The overall retardation can be attributed to the combination of light attenuation, inhibition and competition effects. Moreover, the TiO"2/UV system favors the decomposition of compounds that have stronger adsorption onto the TiO"2 surface. To engineer effective treatment facilities that use the TiO"2/UV system for the treatment of toxic substances in wastewater, the methodology must allow for concerns about adventitious species which are present.