Inhibition of Mordant Dyes Destruction in Fenton Reaction

摘要

Kinetics of destruction of acid and mordant dyes in Fenton reaction was investigated by the use of spectral method. Inhibition of destruction of some mordant dyes was observed. A simple theory for describing this phenomenon was proposed, which is based on consideration of participation of iron ions in complex formation with mordant dye ligands. By the use of chemical software JChem (ChemAxon) it was found that mordant dye exhibiting stability in Fenton solution bears hydroxyl group with high dissociation constant, pK=2.57. On the contrary, another dye bearing hydroxyl with low dissociation constant, pK_1=6.65, does not exhibit any inhibition in oxidation process. UV-Vis spectral studies of the complexes of several mordant dyes prove correlations with their stability in Fenton reaction, however some dyes exhibit no relationship of this kind.