Effects Of Coexisting Of Solids From Nature Waters On Their Sorption For Lindane And Ciprofloxacin

Natural water is a complex heterogeneous coexistence system.biofilms,suspended particles and surface sediments are important components of natural water.They participate in the process of migration and transformation of pollutants in natural water,and to a large extent determine the return of water pollutants.Since the adsorption process of pollutants at the water-solid interface is usually a decisive step in the subsequent environmental behavior of contaminants,it has long been widely concerned by researchers.And there has been a lot of attention to the adsorption of contaminants or coexisting contaminants in a single solid phase aqueous system while little concern about the interaction between the adsorbents(various solid phases in the water)for their adsorption of various pollutants.The biofilms,suspended partic les and sediments that coexist in the same natural water can carry out material excha nge,usually affecting the respective components and structures and even transforming them.The interaction between solid phases is bound to affect the environmental behavior of pollutants in water.Therefore,the study of the interaction between solid matter and the environmental behavior of pollutants in water can help to understand the migration and transformation of pollutants in real water environment.This paper chooses two kinds of organic pollutants,which are widely detected in water environment and are widely concerned: typical organochlorine pesticides-lindane and quinolone antibiotics-ciprofloxacin as target.The isothermal adsorption experiments of different systems were carried out by constructing different combinations of biofilms,suspended particles and sediments.The adsorption characteristics of lindane and ciprofloxacin in different systems were analyzed.The changes of solid phase constituents in the multi-solid phase coexisting system were analyzed by means of fluorescence spectroscopy and other means.The effects of the interaction between solid phases on the adsorption of organic pollutants were discussed.The results show that the adsorption capacity of solid phase to lindane in the single solid phase system is: biofilms> suspended particles> surface sediments.The combination of the solid phase combination in the double-solid phase system with the strongest adsorption capacity of lindane is the combination of biofilms and suspended particles followed by the combination of biofilm a nd surface sediments,the combination of surface sediments and suspended partic les is weakest.The adsorption capacity of ciprofloxacin is the same as that of lindane in the single solid phase system.The strongest combination of solid phase combination of ciprofloxacin in the double-solid phase system is biofilms and surface sediments,followed by the combination of biofilms and suspended particles,the weakest adsorption capacity for the combination of surface sediments and suspended partic les.In the case of the same quality of solid phase,the adsorption capacity of solid phase to lindane is consistent with the content of DOM in the system.The contribution of biofilms,suspended particles and sediments to the adsorption of lindane in the two-phase solid phase system was 45.4%,35.7% and 18.9%,and their contribution to ciprofloxacin was 44.6%,27.2% and 28.3%,respectively.When the coexisting solid phase adsorbs lindane and ciprofloxacin,there is a mutual inhibitory effect between the different solid phases,and the coexisting system with large DOM content is stronger than the adsorption of lindane and ciprofloxacin.In the multi-solid phase coexisting system,the humic acid component of the DOM changes greatly.The redistribution of the components such as humic acid in the DOM leads to the difference of the adsorption characteristics of the organic pollutants in the multi-solid phase adsorption system and the single solid adsorption system.