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Photolysis of Water Solutions of Phenol Olga Chaikovskaya, Irina Sokolova and Rimma Kuznetsova Siberian Physical Technical Institute, Tomsk, sq. Revolution, 1, 634050, Russia
Resulting from more regulations concerning waste water, improvements in the existing methods of water treatment, as well as research into new methods are required. In particular, some new techniques have been proposed that utilize UV light of eximer lasers. The present study was undertaken in the framework of research needed to increase our knowledge of photolysis mechanism of phenol in water. The S0 ® S1 (p p *) absorption band of a water solution of phenol has the following spectral characteristics: l abs=270nm, e max=1600 l mol-1cm-1, the S1® S0 - l fl=300 nm. At increase pH of aqueous solution fall of intensity of fluorescence on a wavelength of the phenol basic form is observed. And also there is the growth of intensity of fluorescence in the range wavelength of 340 nm, that corresponds anion-form of phenol (l abs =290 nm). The intensity of fluorescence of the neutral-form of phenol depends on the excitation wavelength. The dependence on spectral-luminescent properties of phenol on the excitation wavelength and values pH are in agreement with previous studies 1,2. At increase of concentration of phenol in a water solution intensity of fluorescence at first grows, then sharply falls. This fact can be explained to formation of the phenol dimers.In the given work a photolysis of water solutions of phenol is studied by a broad emission band of high-pressure Hg lamp, and also phototransformation of a molecule of phenol in solutions at various pH (water, water with addition KOH) is studied at XeCl* excimer sources emitting with l exc= 308 nm. At the Hg lamp sources emitting of a water solution of phenol in due course observes reduction of absorption in the range wavelength of the basic band of phenol and growth of absorption in the range of 240 nm and 300 nm. Apparently, it is connected to formation of photoproducts. At XeCl* excimer sources emitting fixs formation a photoproduct in the field of 240 nm. Under XeCl* excitation emitting of a water solution of Phenol with addition KOH occurs growth of absorption in the field of 260 nm and 320 nm.This work was financially supported by a Russian Foundation for Basic Research (grand 98-03-03059). References 1 O.Legrini, E.Oliveros and A.M.Braun/Chem.Rev.1993, 93, 671-698.2 G.Kohler and N.Getoff/J.Chem. Soc., Faraday Trans. 1 72, 1976, 2101-2107.
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