气相色谱质谱法测定水中邻苯二甲酸二(2-乙基己基)酯的探讨

Determination of di-(2-ethylhexyl) phthalate in water by gas chromatography-mass spectrometry

目的建立生活饮用水中邻苯二甲酸二(2-乙基己基)酯的气相色谱-质谱测定方法。方法取水样500ml中加正己烷2.00ml,液液萃取静置分层后,取上层正己烷1.00ml于进样瓶中加内标丙酮中苊-d10,菲-d10,-d12混合标准物质50μl(100μg/ml),混匀,气相色谱-质谱联用仪内标法定性定量。结果邻苯二甲酸二(2-乙基己基)酯的色谱分离效果、线性方程相关性均良好,满足实验要求。其相关系数r=0.9987,y=1.9582x+1.6223,方法的检出限为0.3125μg/L,定量限为0.9375μg/L,回收率为87.3%~98.7%。运用本法对灵宝城区五家水厂的出厂水、末梢水进行检测,均未检出邻苯二甲酸二(2-乙基己基)酯(DEHP)。结论该方法方便、快捷、灵敏度高,适用于水中邻苯二甲酸酯类化合物的测定。

Objective To establish a rapid and accurate method for the determination of di - (2-ethylhexyl) phthalate ( DEHP) in drinking water by gas chromatography - mass spectrometry(GC-MS) . Methods 2.00 mln - hexane was added into 500 ml water sample for liquid - liquid extraction of DEHP. 50 μl mixed internal standard substance of Acenaphthene - d10,Phenanthrene - d10 and Chrysene - d12 was added into 1.00 ml supernatant n - hexane. Then 1.00 μl of n - hexane containing internal standard substance was injected for qualitative and quantitative determination of DEHP by GC - MS with internal standard method. Results The linearity and precision of the method were good and can meet the test requirement. The correlation coefficient( r) was 0.998 7,y = 1.958 2x + 1.622 3,and the detection limit was 0.312 5 μg /L,the quantification limit was 0.9375 μg /L,and the recovery was within 87.3% - 98. 7%. The method was applied to the detection of factory water and tape water from five water plants in Lingbao City,and no di - (2-ethylhexyl) phthalate ( DEHP) was detected. Conclusion This method is convenient,rapid,sensitivity and accurate. It is suitable for the qualitative and quantitative determination of DEHP in water samples.