Oxidation rates of phenol

Tratnyek and Hoigne (1994) investigated 25 substituted phenoxide anions for QSARs that can be used to predict rate constants for the reaction of additional phenolic compounds oxidized by chlorine dioxide (OCIO). Correlating oxidation rates of phenols in aqueous solution is complicated by the dissociation of the phenolic hydroxyl group. The undissociated phenol and the phenoxide anion react as independent species and exhibit very different properties. The correlation analysis should be performed on the two sets of rate constants separately. 

On the adsorption of catalase from solutions with a concentration ofC = 1x10 Mm citrate buffer with pH = 3. 02, a dissociation of the enzyme to subunits takes place [2,18]. No matter how the catalase dissociation is initiated, the dissociation process is always accompanied by a cotain loss of catalase activity and optic changes - a shift towards the shortwave region [19]. The catalase tetramer dissociation to monomers [17] runs according to scheme E4 o 4E. For dissolved catalase and for catalase immobilized on soot "NORTT" the dq>endence of the initial oxidation rate of phenol on the initial concentration of the substrate was studied (Fig.2), where A is the absotbance corresponding to the current concentration of the substrate (phenol). The obtained relationships are Ascribed by the equation of Nfichaelis-Menten ... 

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