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Organophosphate esters(OPEs)are one of the families of persistent organic pollutants(POPs).Because of the low cost and excellent flame retardant properties,OPEs are extensively employed as flame retardant and plasticizers applied in furniture,textiles,cable,building materials,insulation materials,coatings,floor polishes,hydraulic fluids and electronic appliances.Because the additives in such products are not chemically bound to the compounds,they can be released to the surrounding environment over the entire life cycle of the products slowly by abrasion and volatilization.Moreover,OPEs have semi-volatility,lipid solubility and tend to combined with particulate matters,which lead to the long-distance transmission of OPEs.In recent years,with the ban of bromine flame retardants(BRFs),OPEs are considered as suitable alternatives for BFRs,and the usage and production increased rapidly.Besides,researches show that OPEs are carcinogenic,neurotoxic,and endocrine disruption.Therefore,OPEs has been one of the hot topics.This study was conducted to establish a analytical method for determination of 13 OPEs in surface water samples.Experimental results showed that the recoveries of 13 OPEs from samples with developed method were in the range of 98%~125%,with relative standard deviations(RSDs)of less than 10%.The correlation coefficients of 13 OPEs in internal standard curve method ranged from 0.998 to 0.999,and the RSDs below 10%.The limit of detections(LODs)in samples ranged from 0.1 to 20 ng/L.On the basis of the establishment of the above detection method for the analysis of the source water samples in 11 cities nationwide waterworks,including the Yangtze River、Songhua River、the Yellow River、 Haihe River、 Liaohe River 、 Huangpu River and Taihu Lake.It was found that the presence of organophosphate esters retardants were detected in the source water of each city’s drinking water plant.The concentrations of TEP,TEHP,TEP and TCPP were 93.91 ng / L,189.02 ng / L,42.53 ng / L and 56.38 ng / L,respectively.The concentration of TEHP was 151.4-236.29 ng / L.As the aroma-substituted OPEs have relatively strong hydrophobicity,their concentrations in the water samples are relatively low.TPP,CDP and EHDPP were not detected in the influent samples.The results showed that the average concentration of OPEs in water was 410.78 ng / L。By the laboratory simulation of the water treatment process section coagulation process,and the optimum removal rate of ozone oxidation process of activated carbon adsorption process,in the case of organic phosphate flame retardant binding practical application down.Through the laboratory test,we found that the choice of aluminum sulfate as coagulant,when the cast aluminum sulfate to aluminum concentration of 20 mg / L,the OPEs for the best removal rate.The removal rate of TDPP,EHDPP,TCP,TBEP,TEHP and TPP reached 100%,the removal rate of CDP was 99.8%,the removal rate of TBP and TCBP was higher,the highest removal rate was 85 % And 73% respectively.TEP,TnPrP,TCEP and TMP removal rate is not high,ranging from 29% to 42%.It was found that the removal rate of ozone-based organophosphate flame retardants was obvious.When the ozone dosage was 3mg / L,the removal rate of benzene-based organic phosphate flame retardants was over 80%,indicating that ozone easily reacts with aromatic compounds.The removal rate of organic phosphoric acid ester flame retardant gradually increased,but when the dosage reached a fixed value,the removal efficiency began to become flat.Considering the dual factors of water plant production investment and pollutant removal,we choose the ozone dosage of 3mg / L,at this time,OPEs removal rate of 68.5%.According to the equation,the initial adsorption rate of Calgon F300 is found to be faster.Langmuir adsorption isotherm model can better fit the adsorption results of OPEs.According to the fitting results,the adsorption capacity of Calgon F300 to OPEs is found at 25 ℃.The addition of Calgon F300 adsorbent combined with the actual hydraulic retention time showed that the total removal rate of OPEs was 81.33%.