Synergistic Degradation Of Organic Wastewater By Vacuum Ultraviolet Coupled With Chemical Oxidation

With the rapid economic development,the problem of environmental pollution in China has become increasingly serious,especially water pollution,has affected the people’s physical health and the normal development of the national economy.Organic wastewater has always been a difficult point in wastewater treatment due to its complex composition,high initial COD,poor biodegradability,and many by-products.Many organic substances have severe toxicity and discharge into water sources without treatment will cause huge environmental disasters.Therefore,this paper starts with the antibiotic wastewater and adopts the vacuum ultraviolet coupled chemical oxidation method to treat such wastewater.The preliminary degradation experiment of the salicylic acid wastewater was carried out.The amoxicillin simulated wastewater and acetonitrile wastewater were explored and tested.The degradation process of acetonitrile wastewater was amplified and satisfactory results were obtained.In the experiment,a vacuum ultraviolet coupled wet catalytic oxidation（CWPO）process was used to treat salicylic acid wastewater.Among them,CuO-ZnO-CoO/γ-Al₂O₃ is used as a wet catalyst,and H₂O₂ is used as an oxygen donor for generating hydroxyl radicals（·OH）.The catalysts were characterized by FT-IR,XRD,SEM and EDS.The degradation rate of salicylic acid（%）,COD value（mg/L）and COD removal rate（%）were used as catalysts in the experiment.The effects of salicylic acid wastewater concentration,catalyst usage,solution pH,H₂O₂dosage and temperature on the coupling degradation process were investigated,and the optimal experimental conditions were obtained.The experimental results show that the CWPO/H₂O₂/VUV coupled process can achieve high degradation efficiency for salicylic acid degradation.It can degrade 100%salicylic acid within 10 minutes and remove 98.48%of COD within 20 minutes.At the same time,vacuum-ultraviolet coupled chemical oxidation method is effective for the degradation of amoxicillin simulated wastewater and acetonitrile wastewater.Among them,the degradation of the actual wastewater of acetonitrile is an exothermic process.The degradation process is affected by the pH of the solution.The factor that affects the COD removal rate is H₂O₂ and the amount of catalyst.In order to scale up the acetonitrile wastewater,CuO-ZnO-CoO is used.Theγ-Al₂O₃catalyst was shaped to explore the useful life of the catalyst after molding.The experimental results show that when the wastewater treatment capacity reaches 550L,the performance of the catalyst is affected at this time,and the performance of the catalyst will be restored after activation.The scale-up experiment of acetonitrile wastewater shows that,after 60 min of coupling degradation,the acetonitrile wastewater with a COD value of 98400 mg/L can be reduced to 5,672 mg/L.At this time,the COD removal rate reaches 94.23%.The results show that the coupled degradation is used as a high-concentration organic wastewater.The pretreatment method has high efficiency and can reduce the COD value of the wastewater in a short time.