Study On The Microwave Induced Catalytic Oxidation Of Dye Wastewater

Basing on the situation of dye wastewater:large discharge,high organic mattercontents,deep color and difficult to degrade, processing cost etc. With Cationic azo dyeacid red B and cationic basic fuchsin as target pollutants,with modified granularactivated carbon as carrier to prepare metal ion catalyst.Using batch experiments tostudy the characteristics and laws of microwave induced catalytic oxidationdegradation.Through conditional test, orthogonal test, comparison test, repeated test anddynamic test discussed catalyst carrier preparation condition, catalyst slection,the besttreatment conditions of two kinds of dye,and dynamic characteristic and rules of ORPvariations.Through the catalyst characterization tests:the larger carrier specific surface areawas,the higher dye’s degradation rate.Microwave modification conditions had littleeffect on surface functional groups species.But,had obvious effect on the proportion oftotal oxygen functional groups,which were corresponding to their effect on degradiationof dye. Through the single factor experiments:For acid red B,the optimal processingconditions were:initial pH value was3,the dosage of catalyst Fe³⁺-Cu²⁺/AC was1000mg/L,H₂O₂dosage was101.1mg/L,the microwave power was300w,after5min’sirradiation,acid red B removal rate was over99%.For basic fuchsin,the optimalprocessing conditions were:initial pH value was2.5,catalyst dosage was1000mg/L,H₂O₂dosage was67.4mg/L,the microwave power was300w,after7min’s irradiation,basicfuchsin removal rate was over94%.Through the contrast experiment:microwave oncatalytic oxidation degradation of simulated dye wastewater was necessary.Through thecatalyst reuse tests:after10times reused,the removal rate of simulated dyewastewater,was still over90%.Through orthogonal experiments obtained:the order offactors infect degradiation of acid red B and basic fuchsin respectively were:irradiationtime>microwave power>H₂O₂dosage and microwave power>irradiation time>H₂O₂dosage.During the reaction of microwave irradiation system, there was no correspondingrelationship between reaction rate of dye and solution ORP.The degradation occured onthe solid-liquid interface between catalyst and solution,degradation depends on catalystsurface properties.After the reaction of microwave irradiation,there was good corresponding relationship between dye’s degradiation and solution ORP.When thereaction progressed,the dye concentration decreased and solution ORP increased slowly,the degradation depends on the oxidizing species of the solution.In the system of “microwave/catalyst/H₂O₂”,the degradation of acid red B andbasic fuchsin conformed first-order reaction kinetics model dC/dt=-k（C-C_e）,reactioncoefficient were0.63min^-1and0.47min^-1.This study investigated the effects of experimental conditions on the reactionprocess,the different reaction systems for degradation of dye wastewater and thecharacteristics of kinetics process.Understanded and revealed the laws of microwaveinduced catalytic oxidation degradation of acid red B and basic fuchsin.Suppliedefficiently and economical treatment of dye wastewater with technology support andreference.Also supplied a technology to solve the problem of catalyst recovery andmetal ion second pollution.