Study On Modification Of Zeolite And Degradation Of Dye Wastewater

With the rapid development of the industry,the discharge of organic dye wastewater is increasing,which poses a great threat to human health and ecological balance.The waste water is characterized by high concentration,complex composition and poor biodegradability.So we call it typical refractory organic wastewater.Catalytic wet oxidation technology could effectively treat this kind of wastewater,but the active component of catalyst is easy to be lost,which leads to the secondary pollution of water.Therefore,the research of efficient and stable catalyst becomes the hotspot of catalytic wet oxidation technology.In this paper,the effects of alkali atreatment and metal loading on the catalytic activity and stability of ZSM-5 zeolite were studied by using CODcr removal rate and metal ion dissolution quantity as evaluation index,and optimize the modification conditions.The effect of the modified catalyst on the degradation of simulated dye wastewater and actual industry wastewater under UVlight irradiation was investigated,and the optimum process was determined.At zhe same time,the degradation kinetics of simulated wastewater was studied,and the degradation pathway of acid red GR was also discussed.Using alkali and metal Cu,Zn,Ce modified ZSM-5 zeolite,and determine the optimum modification conditions.The best modification conditions were confirmed as follows: Na OH solution is 0.2mol/L;the molar ratio of Cu / Zn / Ce is 8: 4: 1.On this basis,the preparation method was investigated.The results showed that the catalyst prepared by sol gel method was better.Through the characterization of catalyst analysis showed that alkali atreatment did not destroye the basic structure of ZSM-5 zeolite.With the increase of the loading amount of metal ions,agglomeration became more and more obvious,and proper Ce doping not only promoted the dispersion of Cu O and Zn O,but also reduce its particle size.In addition,the catalyst prepared by the sol gel method has smaller particle size and more uniform particle size.The effect of different factors on the degradation of acid red GR simulated wastewater by Cu-Zn-Ce / Z-AT catalyst under UV assisted condition was investigated by single factor experiment.,then through orthogonal experiment to optimize the process.The optimum conditions were as follows: reaction time 90 min,reaction temperature 70 ?,catalyst dosage 0.20 g,initial p H 4,hydrogen peroxide dosage 0.6m L.Under these conditions,the decolorization rate and CODCr removal rate of acid red GR simulated wastewater were 99.73% and 99.86%,respectively.By using detection means of UV-Vis,IR and GC-MS spectrum analysis,the degradation process of acid red GR degradation by UV assisted catalytic wet air oxidation was studied.UV-assisted catalytic wet oxidation first destroy the azo bond in the dye structure leading to lose its color,and then destroys the benzene ring and the naphthalene ring in the structure to generate small molecular substances.the kinetics study on Cu-Zn-Ce / Z-AT degrade acid red GR simulated wastewater,The apparent kinetic equation was:The effect of Cu-Zn-Ce / Z-AT catalyst on the actual wastewater that botain from sugar-making enterprise in Jiangxi Province was studied.The results showed that the treatment effect of the catalyst was ideal.