Study On Combination Mechanism Of Dissolved Organic Matter And New Pollutant PPCPs In Urban Environment

Carbamazepine?CBZ?is an anti-epileptic drug which was widely used in the world.It can detect the presence of CBZ in urban water environment due to the large amount of dissolved organic matter in urban water environment.It may interact with CBZ,which causes the fate and migration of CBZ in urban water environment to be affected.Therefore,it has great significance to study the mechanism and mechanism of DOM and CBZ in urban water environment.In this paper,the effluent from the composting leachate of different treatment units was collected to study the changes of the fluorescence characteristics and composition of DOM after different treatments,and the effects of DOM and nutrients on the distribution of heavy metals and CBZ during the combined treatment of leachate.Excitation-emission matrix?EEM?fluorescence spectroscopy showed that the content of fulvic acid,humic substances and protein-like substances decreased gradually as compost leachate was continuously treated by different treatment units.Identification of a fulvic acid-like component?C1?,three humic acid components?C2,C3 and C4?and three protein components?C5,C6 and C7?in the composting leachate DOM by parallel factor analysis.The anaerobic-aerobic process removes most of the tyrosine-like components?C7?and tryptophan-like components?C6?and a small amount of humic-like components?C2?,while the membrane bioreactor shows a good removal of protein-like materials.Ultrafiltration membrane treatment has a good removal effect on fulvic acid-like,humic-like substances and other difficult biodegradable compounds,while reverse osmosis membrane treatment has good removal effects on humic-like substances and protein-like substances.Correlation analysis showed that Mn and Cr were mainly related to protein-like components and nutrients in composting leachate.Ni and Pb are combined with fulvic-like acids,humic-like and protein-like components,Co and Zn interact with inorganic nitrogen and total phosphorus,and Cd interacts only with inorganic nitrogen.CBZ is combined with TSS,TOC and small molecular protein substances and its migration and transformation risk in aqueous environment is significantly reduced after combined treatment.This paper also studies the changes of the nature and structural characteristics of DOM in road rainwater runoff by GS treatment,and the effect of this change on the complexation of CBZ and DOM.The spectral technique is used to explore the relationship between CBZ and DOM.Different binding characteristics to understand the migration and biogeochemical properties of CBZ in water environment.The results of 2D-COS showed that the DOM of road rainwater runoff showed more binding sites with CBZ than the effluent DOM.The treatment of GS can greatly affect the binding sequence of CBZ and DOM fluorophores.The results also indicate that the log _KM values of protein-like substances are higher than those of other fluorescent components,suggesting that protein-like fluorescent substances may play a crucial role in the geochemical behavior of CBZ.At the same time,the log _KM of different components of DOM after GS treatment is significantly increased while the treatment of GS can also remove most of the fluorescent DOM,which indicates that GS treatment can effectively reduce the risk of CBZ in water environment.