The Study On Photocatalytic Degradation Of Water Organic Pollutants In A Pharmaceutical Factory In Dalian

Due to the influence of human activities,water pollution is becoming more and more serious.All kinds of organic pollutants which can't be naturally degraded are continuously accumulated and strengthened through the biological network,which damages the ecological environment and health.Therefore,it is extremely important for regional water environment security to improve water pollution treatment rates and apply "sustainable" water treatment technology.Photocatalytic technology has great potential for advanced treatment of wastewater pollutants.Some semiconductor photocatalytic materials with high activity,high selectivity and high stability have been developed.Carbon nitride is one of the hot research fields.Based on the contradiction between supply and demand of water resources and the problem of water environment in Dalia,the field investigation method was used to sample,test and evaluate the groundwater of a pharmaceutical factory.The evaluation results show that the depth of the groundwater in the study area is shallow,the water quality grade is heavy polluted,and a variety of water pollutants exceed the standard.In this regard,the photocatalytic method is introduced to deal with the water pollution in the area.First,the Yb2O3/g-C₃N₄,La₂O₃/g-C₃N₄ and Ag-La₂O₃/g-C₃N₄ series composite photocatalysts are prepared.Then,FESEM,TEM,EDS,XRD,FTIR,DRS,PL,XPS and other technologies are used to analyze and characterize materials.It is confirmed that the materials have excellent structure and photochemical properties.Finally,the composites were used to degrade the excess pollutants.The experimental results show that three series materials can be used as stable and efficient composite photocatalysts to deal with the problem of excessive organic pollutants?such as phenol,tetracycline hydrochloride,etc.?in water.Adoption of the controlled trial method,it is determined that in this photocatalytic system,the degradation effect reaches the best level when the catalyst content is 2 g/L and the reaction solution remains neutral.Electron–hole separation is important for the photocatalytic effect.Electrons,holes,superoxide radicals as well as hydroxyl radicals dominate the photocatalytic reaction.The surface plasmon resonance?SPR?effect and "electron trap" function of Ag nanocrystals in Ag-La₂O₃/g-C₃N₄ series materials promote the electron–hole separation,and enhance the photocatalytic activity of the materials.In this study,the high-performance composite photocatalysts were applied to the degradation of organic pollutants in water,which provided the experimental basis and theoretical basis for the practical application of photocatalysis technology in deep water treatment.