为分析再生水中消毒副产物,采用顶空进样-毛细管气相色谱-质谱联用技术和选择性离子定量分析,通过优化顶空进样条件和色谱、质谱检测条件,建立了再生水中三卤甲烷类消毒副产物快速检测方法.研究结果表明,在三卤甲烷(三氯甲烷、一溴二氯甲烷、二溴一氯甲烷、三溴甲烷)4种卤代烃的质谱图中,含有2个卤素原子的质谱离子(A)及其同位素离子(A+2、A+4)的丰度远远高于其他质谱离子,作为定量分析离子具有较强的特异性、选择性、代表性,有利于提高方法的灵敏度.以选择性离子∑SIM(83,85,87)、∑SIM(127,l29,131)、∑SIM(171,173,175)作为再生水中三卤甲烷外标法定量依据,方法的回收率为83.4%～112.2%,相对标准偏差(RSD)为3.5%～8.2%,检出限小于0.21μg/L城市再生水中三卤甲烷在100μg/L以上.%In order to analyze the disinfection by-products in reclaimed water, a rapid analyzing method of the THMs (Trihalomethanes), a types of the disinfection by-product, has been developed by using static headspace sampling, capillary gas chromatography, mass spectrometry and ion selective quantitative analysis through the optimization of headspace sampling, chromatography and mass spectrometry testing conditions. The results show that the fragment ions (A) of connecting two halogen atoms and their isotope ions ( A + 2, A + 4) are of much higher peak abundance than other mass ions in the mass spectrum of four THMs (including chloroform, dichlorobromomethane, dibromochloroethane, bromoform ). It is highly specific, selective and representative to choose the character ions for the THMs quantitative analysis, and at the same time the method sensitivity is also improved. An external standard method is used to quantitively analyze the THMs in the reclaimed water based on the sum of selected ion monitoring (ΣSIM) of m/z 83, 85, 87 for a chloroform and a dichlorobromomethane, m/z 127, 129, 131 for dibromochloroethane, and m/z 171, 173, 175 for bromoform. The method recoveries range from 83.4％ to 112. 2％ , the relative standard deviations (RSD) are from 3.5 percent to 8.2 percent, and the detection limits are less than 0. 21 μg / L. THMs concentration of the reclaimed water is above 100 μg/L.
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