title: Mechanism and kinetic model for the decolorization of the azo dye Reactive Black 5 by hydrogen peroxide and UV radiation.
abstract: A kinetic model for the decolorization of C.I. Reactive Black 5 by the combination of hydrogen peroxide and UV radiation was developed based on experimental results and known chemical and photochemical reactions. The observed kinetic reaction coefficient was determined and correlated as a function of hydrogen peroxide concentration and UV intensity. The validity of the rate expression was tested experimentally in a parameterization study. The decolorization rate follows pseudo-first order kinetics with respect to dye concentration. The rate increases linearly with UV intensity and nonlinearly with increasing hydrogen peroxide concentration, going from a linear relationship at low H(2)O(2) concentrations to a maximum as hydrogen peroxide concentration continues to increase. The decolorization rate expression derived from the proposed reaction mechanism was reconciled with that used for correlating the experimental data.
authors.affiliation: Institut für Verfahrenstechnik, Technische Universität Berlin, Strasse des 17. Juni 135, 10623, Berlin, Germany. abdallah.moheyeldein@nottingham.ac.uk
authors.forename: A
authors.initials: A
authors.lastname: Mohey El-Dein
authors.forename: J A
authors.initials: JA
authors.lastname: Libra
authors.forename: U
authors.initials: U
authors.lastname: Wiesmann
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D009282:Naphthalenesulfonates / Q000737:chemistry*; D010777:Photochemistry; D012016:Reference Values; D014466:Ultraviolet Rays; D018508:Water Purification / Q000379:methods
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D009282:Naphthalenesulfonates; D006861:Hydrogen Peroxide; C063421:Remazol black B