Distribution Of PAEs In The Songhua River And The Removal Research

Phthalate acid esters (PAEs) are widely used in toys, cosmetics.Pharmaceutical and Personal Care Products in recent years, and become one of the most pollutants in aquatic environment like river and lake. They have received an extensive attention because of a series of endocrine disrupting activities such as the estrogenic activity.Various PAEs have been detected in Yangtze river, Yellow River and other waters in China. However, there has been little systematic monitoring of occurrence of PAEs along the Songhua River in China, so it’s necessary to investigate the levels of the Songhua River (surface water, groundwater). The purpose of the study was to investigate the fate of six PAEs in the Songhua River(passed through four cities Songyuan, Harbin, Jiamusi, Tongjiang), provide the distributed feature information of PAEs in the Songhua River. The results showed that DEHP was the most frequently detected with high concentrations ranging ND-78.87μg/L in surface water and ND-356.14μg/L in groundwater. We can see from the findings of the Songhua River water that spatial distribution of organic pollutants in groundwater and surface water had a good consistency, except that DEHP concentration in harbin downstream groundwater sampling points was significantly higher than that of surface water, the main reason may be that chemical plants, plastics factories and other enterprises are intensive near this sampling points, groundwater are affected by the emissions of industrial enterprises are obvious.Aimed at the high levels of water, we employed different treatment processes such as UV/H2O2and UV/US to degrade PAEs. The effects of H2O2concentration, PAEs initial concentration and pH of PAEs solution were investigated. The results show that degradation efficiency of DMP and DEP at UV/H2O2mode is proved to be superior to that at UV and H2O2single treatment under the given experimental conditions. Degradation efficiency increases with increasing H2O2concentration, decreases with increasing PAEs initial concentration and independent on pH value. When PAEs initial concentration is5mg/L and H2O2concentration is330mg/L degradation efficiency of DMP and DEP can reach to80.7%and84%respectively after120min degradation.When UV wascombined with US, degradation efficiency of DMP and DEP could reach to45.3%and50%, respectively after120min degradation. The degradation efficiency of DMP and DEP at UV/USwas proved to be inferior to that at UV/H2O2may be due to low frequency of the ultrasonic generator. Moreover, degradation efficiency of PAEs can be increased if the frequency is increased, UV/US will have a good prospect in the PAEs treatment as a fast and clean process.