Catalytic effect of supported metal ion complexes on the induced oxidative degradation of pyrocatechol violet by hydrogen peroxide.

摘要: Abstract Kinetics of the oxidative degradation pyrocatechol violet dye (PCV) {2-[(3,4-dihydroxyphenyl)(3-hydroxy-4-oxocyclohexa-2,5-dien-1-ylidene) methyl]-benzenesulfonic acid} by H 2 O catalyzed supported transition metal complexes have been studied. The reaction was followed conventional UV–vis spectrophotometer at λ max =440 nm in a buffer solution pH 5.1. supports used were silica gel and cation exchange resins (Dowex-50W, 8% DVB), while [Cu(amm) 4 ] 2+ , [Cu(en) [Cu(ma) [Co(amm) 6 [Ni(amm) (amm=ammonia, en=ethylenediamine, ma=methylamine). exhibited first-order kinetics with respect to [PCV] [H ]. reactivity catalysts is correlated redox potential ions, type support, amount complexes. rate increases increasing pH addition NaCl. Addition SDS CTAB showed inhibiting effects. enthalpy-controlled as confirmed from isokinetic relationship. A mechanism involved generation free radicals an oxidant has proposed.