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SDS micellar solution containing 1-propanol, 2-propanol, 1pentanol, or 1-octanol show that the alcohol increases water penetration into the micellar interface structure. The degree of water penetration depends on the alkyl chain of the alcohol and varies in the order 1-propanol < 2-propanol s 2-pentanol < 1-octanol. Analysis of the trend of deuterium modulation for deuteriated alcohols (2-propanol-d7 and l-octanoW17 in D2Q and in H20) gives direct evidence that 2-propanol, for an alcohol/ surfactant mole ratio less than 0.75, is located at the micellar interface whereas 1-octanol is located deeper into the micelle. The relative TMB+ yield enhancement by alcohol increases to a maximum and then decreases. The initial yield enhancement correlates with the degree of water penetration into the micelle, but the maximum yield enhancement is suggested to be related to the degree of water organization at the micellar surface due to specific perturbing effects on the micellar structure dependent upon the alcohol structure.Acknowledgment. This research was supported by the Department of Energy, Office of Basic Energy Sciences. P.B. thanks the Italian Ministry of Public Instruction for partial financial support.

A kinetic model has been developed, taking into account both decomposition of ozone molecules and interactions between ozone and hydrogen peroxide for formation of hydroxyl radical and subsequent reactions. Experiments were carried out at 25°C in the pH range of 3 to 13, indicating that the depletion rate of ozone increases with the concentrations of ozone, hydrogen peroxide and hydroxyl ion, as predicted by the kinetic model. Adverse scavenging reactions, however, also play significant roles at sufficient concentration ratios of hydrogen peroxide to ozone and high concentrations of hydroxyl ion in reducing the depletion rate. Results of this research suggest, that it is most desirable to conduct the peroxone oxidation for pollutant destruction by the hydroxyl radical reaction in alkaline solutions of pH below 1 I , while maintaining about the same concentration of ozone and hydrogen peroxide.

Cobalt(II) 4,4',4",4"'-tetrasulfophthalocyanine, ConTSP, covalently linked to the surface of titanium dioxide particles, Ti02-CoTSP, is shown to be an effective photocatalyst for the oxidation of sulfur(IV) to sulfur(VI) in aqueous suspensions. Upon band-gap illumination of the semiconductor, Ti02, conduction-band electrons and valence-band holes are separated; the electrons are channeled to the bound ConTSP complex resulting in the reduction of dioxygen while the holes react with adsorbed S(IV) to produce S(VI) in the form of sulfate. The formation of S(V) radicals indicates that the reaction proceeds via successive one-electron transfers. Quantum yields in excess of unity were observed and attributed to desorption of S03*from the Ti02 surface and subsequent initiation of a homogeneous free radical chain reaction. Observed quantum yields between 0.5 and 300 depend on the concentration and nature of free radical inhibitors present in the suspension. A kinetic model that integrates the photon absorption properties of the solid, the heterogeneous redox reactions on the catalyst surface, and the homogeneous reactions of S(IV) is presented.

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