Article ID Journal Published Year Pages File Type
161306 Chemical Engineering Science 2005 12 Pages PDF
Abstract

The effect of oxygen on the reaction kinetics of the photocatalytic oxidation of dichloroacetic acid at pH below the titanium dioxide isoelectric point (pH from 5 to 4) was studied. A kinetic scheme based on the direct hole attack to the dichloracetate ion in conjunction with the classical role of oxygen acting as an electron acceptor is proposed. Oxygen also intervenes in a direct addition reaction to one of the intermediate reaction products. Experiments were conducted in a well-mixed, small, flat plate reactor employing Aldrich titanium dioxide as the photocatalyst in the suspension mode and using polychromatic irradiation with energy in the range from 275 to 385 nm in wavelength. A complete mathematical model, including the effect of the absorbed radiation intensities and catalyst concentration was developed. Experimental data agree well with theoretical predictions employing just two kinetic parameters derived from the proposed reaction mechanism.

Related Topics
Physical Sciences and Engineering Chemical Engineering Chemical Engineering (General)
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