Experimental Study On Photocatalytic Oxidation Of Nitrobenzene Wastewater By Fe And N Doped TiO₂

Dyestuff wastewater is a difficult industrial wastewater with high organic concentration and high chroma.If it is not treated effectively,it will cause serious pollution to the environment.Photocatalytic oxidation is one of the effective methods to treat refractory organic wastewater,and the performance of photocatalyst has a great influence on the treatment effect.TiO₂ photocatalyst is currently the most widely used photocatalyst,among which modification and loading are one of the research focuses.In this study,Fe,N co-doped TiO₂/ACFs photocatalytic oxidation treatment of reactive brilliant red dye wastewater was mainly carried out,and the technical basis for its application in the field of dye wastewater treatment was provided.Taking reactive brilliant red X-3B dye wastewater as the research object,the preparation of TiO₂/ACFs photocatalyst and the effect of photocatalytic oxidation of reactive brilliant red X-3B dye wastewater were studied through small-scale experiments.Fe,N co-doped TiO₂/ACFs photocatalyst The preparation of catalyst and the effect of photocatalytic oxidation of reactive brilliant red X-3B dye wastewater,and the optimal process parameters were determined by orthogonal experiments.The treatment effect of wastewater.The TiO₂/ACFs photocatalyst was prepared by artificial impregnation-pulling method with activated carbon fiber as the carrier.The test results show that the TiO₂/ACFs photocatalyst prepared under the conditions of calcination temperature of 450℃,calcination time of 2h,and coating times of 4 times has the best treatment effect.The color removal rate and COD removal rate of X-3B dye wastewater reached 92.81% and 76.87%,respectively.Ferric nitrate nonahydrate and urea were divided into iron sources and nitrogen sources to modify TiO₂ by ion doping.Different Fe and N doping amounts have certain effects on the photocatalytic performance of the photocatalyst.At a calcination time of 2h and a calcination temperature of 450℃,the ratio of Fe doping amount n（Fe）: n（Ti）is 0.9%（molar fraction）and the ratio of N doping amount n（N）: n（Ti）is 0.2 The Fe,N co-doped TiO₂/AFCs catalyst prepared under the condition of（molar fraction）has good catalytic performance.Under the irradiation of ultraviolet light,the amount of aeration and the dosage of catalyst have a certain influence on the photooxidation effect of the catalyst.The optimal reaction conditions determined by the orthogonal test are: the p H value of the wastewater is 3,the dosage of The dosage is 0.15 g,the dosage of H2O2 is 1.5m L,the aeration rate is 0.7m3/h,the Fe,N co-doped TiO₂/AFCs catalyst has a good water effluent effect,and the reaction system is relatively stable,and the average chromaticity removal rate reaches 97.40 %,and the average COD removal rate reached 91.74%.Under natural light irradiation,Fe,N co-doped TiO₂/ACFs photocatalytic oxidation of reactive brilliant red dye wastewater also has a good treatment effect.When the concentration of oxidant H2O2 reaches 1.0ml/L,the catalytic effect reaches a higher value,and the chromaticity and COD are removed.The rates were 93.16% and 86.49%,respectively.Fe,N co-doping supported TiO₂/AFCs catalyst improves the photocatalytic oxidation effect,and the loading overcomes the easy agglomeration of traditional powder TiO₂ in solution.Fe,N doping reduces the recombination rate of electron-hole pairs,effectively Improve the photocatalytic performance of TiO₂.The method has a prospect of popularization and application in the field of refractory organic wastewater treatment.