Kinetics of the ozone oxidation of Reactive Orange 16 azo-dye in aqueous solution

Ozone oxidation kinetics of Reactive Blue 19 anthraquinone dye in a tubular in situ ozone generator and reactor: Modeling and sensitivity analyses

“…Hence the second order kinetics rate constant obtained in this research cannot be compared to the reported results of the literature for RB-19 dye ozonation. There have been some attempts recently to fit a second order rate equation to the primary decolorization reaction for other anthraquinone and azo dyes [25][26][27]. Gomes et al, [25] attempted to fit rate data from a 15-min time period to a second-order rate model without considering diffusion effects.…”

“…An implicit solution for stiff problems available in MATLAB software (ode23tb) was used to solve the set of equations (Eqs. (17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)) in the bulk liquid. The solutions of the equations for the film calculates the values of E and D at time t and these values are used in the mass balance equation for bulk liquid and the reactor system (Eqs.…”

“…The values of E and D become the input to the set of mass balance equations (Eqs. (17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)) for the bulk liquid whose solution calculates the value of concentrations of dye, dissolved ozone, primary products (P1) and secondary products (P2) at the next time step (t = 0 + Dt). Then, the program goes back to calculate the new values of Ha, E inst , and R based on this new value of dye concentration in bulk.…”

“…(3)(4)(5)(6) and (17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)) is used to extract the two rate constants for reaction between ozone and dye (k 1 ), and ozone and primary products (k 2 ) in two steps. In the first step, the reaction rate constant value, k 1 was determined by fitting the model output for dye concentration to the experimental data.…”

Pesticide degradation in water using atmospheric air cold plasma

“…At low pH a slow reaction takes place between the dissolved ozone and hydrogen peroxide which result in the formation of hydroxyl radicals, but these reactions are greatly accelerated at high pH. Ozone cleaves double bonds and direct reactions with compounds such as OH, CH 3 , OCH 3 , NH 2 also leads to oxidation [52][53][54]. The following are few chemical reactions which might take place during and post plasma treatments.…”