Study On The Variation Dynamics And Removal Of Triclosan In Tap Water Treatment Process

Triclosan(2,4,4-trichloro-2-hydroxydiphenyl ether, TCS) as an efficient antimicrobial agent is prevalent all around the word. However, its negative to the environment problem has caused widespread concern. This research was aimed to analyse TCS current situation in Xiamen Gaodian Drinking Water Treatment Plant by establishing TCS detection method of GC/MS and HPLC-PDA under Lab circumstance. And research on removal of TCS by Ultraviolet(UV), Chlorine dioxide(ClO2) or UV and Chlorine dioxide combined at the same time.Firstly, establishing TCS detetion method: Solid Phase Extraction(SPE)- GC/MS.This solution Method Detetion Limited(MDL) was 0.66μg?L-1, Instrument Detetion Limited(IDL) was 1.31μg?L-1. Recovery rate was 83.87~94.29%, RSD was2.31~3.11%. This solution was accurate enough to detect TCS in the water. TCS HPLC-PDA detetion method was established. This solution MDL was4.22μg?L-1, IDL was 9.55μg?L-1. Recovery rate was 92.74~98.87%, RSD was 2.81~4.31%. This solution was accurate enough to detect TCS in the Lab circumstance.TCS detetion in Xiamen Gaodian Drinking Water Treatment Plant was from March to November at the year of 2014. It revealed that TCS concentration was47.17ng?L-1~33.02ug?L-1, TCS had its highest concentration from May to July, TCS concentration was 3.78~33.02ug?L-1 in these three months. TCS was2.96ng?L-1~15.44ug?L-1 during the process, and it achieved its highest removal rate in May,June and November.The three process including UV, ClO2 or UV/ClO2 removed TCS. The results show that UV/ClO2 process can effectively remove TCS and has a synergistic effect.when light intensity was 6.5μW?cm-2, dose of ClO2 was 0.5mg/L and the concentration of TCS was300μg?L-1, the separate of UV and ClO2 in 1min to the removal TCS reached only 5.23% and 84.93% respectively. Removal rate may up to99.13% after 1 min degradation through the UV/Cl O2 combined process.Degradation products of TCS were investigated by GC/MS. Degradation of TCS by the processes of UV, ClO2 and UV/ClO2 also indicated that the main degradation products of the TCS are 2, 4- dichlorophenol(2,4-DCP),2,7-dichlorodibenzo-p-dioxin(2,7-DCDD), etc.