The Study On Oxidative Degradation Of DMF Use Molecular Sieve Loaded Fe/TiO₂ As A Catalyst For Heterogeneous Fenton Reaction

N,N-dimethylformamide（DMF）is the raw material for many chemical products.And good polarity makes it often used as an organic solvent for industrial production and has a wide range of applications.The wastewater containing DMF is treated by physical,chemical and biological methods.In general,the use of separate processing techniques is often not particularly desirable,so a variety of methods are commonly used.The treatment of DMF wastewater is of low efficiency,complicated process and high cost,there is no ideal method so far.Therefore,it is necessary to study the treatment technology of DMF in degrading wastewater.This paper mainly studies the degradation of DMF based on heterogeneous Fenton oxidation technology.Combined with photocatalytic oxidation technology.The two methods are combined and loaded on the molecular sieve carrier and a photocatalyst material that can be used for oxidation and degradation of DMF wastewater is prepared because of all of them are produced by reaction,OH,organic matter degradation.The preparation process of the catalyst and the degradation experiment of DMF were studied.In order to produce excellent molecular sieve catalysts,the effect of molecular sieve pretreatment was studied.Acid type,acid concentration and acid treatment time were the main factors.The removal rate of methyl orange was simulated as the adsorption capacity of molecular sieve to determine the performance of molecular sieve.The preparation conditions of 5 catalysts namely Fe concentration,TiO2 concentration,dispersant concentration,binder content and roasting temperature were further studied.The optimum preparation conditions of molecular sieve catalyst were determined by orthogonal analysis.The results showed that the order of influencing factors from strong to weak was TiO2 concentration,Fe³⁺loaded concentration,roasting temperature,dispersant concentration and binder content.Fe-tio2 molecular sieve catalyst was synthesized by the optimum preparation conditions.The effects of the initial pH of DMF solution,concentration of H2O2,the amount of catalyst,the initial concentration of DMF and the intensity of light intensity on the catalytic oxidation degradation of DMF were studied.The catalyst performance and stability were measured by the degradation rate of DMF.The results showed that the pH value was 3.0,the concentration of H2O2 was 10g/L,the catalyst was injected with 5g/200mL,the initial concentration of DMF was 2000mg/L,and the uv lamp power was 24W.The catalyst has the best degradation effect on DMF,and the catalyst still has good catalytic activity after repeated use.SEM and TEM electron microscopy,EDS,XRD and BET were used to characterize the catalyst materials、elemental analysis,material crystal characterization,specific surface area and other properties.The results showed that Fe and TiO2 were successfully loaded on the molecular sieve active surface.Non-homogeneous Fenton and photocatalysis catalyze the degradation of DMF.The experimental data of DMF were oxidized by non-homogeneous Fenton molecular sieve catalyst,and the change of DMF concentration over time was analyzed.It was found that 1/C（DMF）in each single factor was strongly correlated with time,and the non-homogeneous Fenton degradation DMF was consistent with the second-order reaction kinetics model.