The Decoloration Treatment Of Reactive Brilliant Red X-3B

Azo dyes have the most types, among which the reative dyes are most widely used.Ln this paper, the typical slngle azo dye reactive brilliant red X-3B is chosen as arepresentative model compounds to study. Three k lnds of methods, namely Fentonreagent、ozone and Fe-C(iron carbon lnternal electrolysis), are used to decolor anddegrade the simulation wastewater. The results are applied to treat the actual dye lngwastewater, and the best processlng scheme is put forward.When Fenton reagent was applied to oxidize the100mg/L simulation X-3B,solution has been optimized though the orthogonal experiment and s lngle factorexperiment. The results revealed that the optimum reaction conditions are pH=3;hydrogen peroxide(30%) dosage is0.5mmol/L; C(H2O2)/C(Fe2SO4) is10; and thedecoloration and TOC removal efficiencies could reach98.93%and48.81%.Furthermore, the study on the dynamics showed that the color removal met thesecond-order reaction. The calculated activation energy of X-3B ln the Fenton reactionsystem is about99.15kJ/mol accordlng to the Arrhenius Law.Ozone is an excellent oxidation reagent, which has achieved desirable effect onreactive brilliant red. When the ozone dosage is92.5mg/L, the decolorization and CODremoval rate are99%and42.1%. pH is an important factor,while Alkallne condition ispreferred to neutral and acidic conditions and it drops as the reaction processes. Sallnitycan hlnder the lndirect ozone reaction, which shows up the decllne of COD removal rate.O3/UV had little impact on the decolorization rate, but could lncrease the removal ratioof COD. Ozone acts on the X-3B conforms the first-order reaction.Fe-C is considered to be a promislng method for dyelng wastewater treatment.Beaker experiment lnitiatively proved Fe-C has good effect on high concentrationsimulation wastewater at the acidic and neutral conditions. EDTA caused10%decolorlng drops proved that iron ion has certaln effect on adsorption flocculationfunction. Fe-C column static test showed that the removal efficiency lncreased, alongwith the lncrease of aeration quantity. The effect ln acidic and neutral conditions is farbetter than alkallne condition, if do not exist buffer system, the solution will quickly riseto alkallne. Ozone lntegrated with Fe-C could improved the remove ratios of color andCOD about25%and15%compared to the same condition without Fe-C. Fe-C columndynamic test showed that on the condition of HRT is2h and aeration quantity is600mL/min, the remove ratios of color and COD lncreased35%and40%respectivelycompared to the unaeration terms. Color and COD removal rates lncrease with HRTlncrease, when HRT is less than4h; and malntaln on84%and73%when it is more than 4h. The degradation of Fe-C is in accordance of the second order reaction.Comparlng the treatment effects and economy of the three methods on practicalwastewater, Ozone is chosen as the suggested method. Fenton reagent obtalned goodresult, while the wastewater is alkallne, the cost on adjustlng pH to acid is high. Fe-Cneeds long time and high cost on the practical wastewater treatment.