分散液液微萃取气相色谱质谱联用法测定海水中三氯苯

本文建立了分散液液微萃取结合气相色谱质谱联用法测定海水中三氯苯(TCBs)的方法。考察了萃取剂和分散剂的种类、体积、超声萃取时间、萃取温度等对模拟海水加标样品的萃取效率的影响,得到最佳萃取实验条件为:以丙酮为分散剂、氯苯为萃取剂,超声萃取时间为10 min,萃取温度为25℃。样品的加标回收率为97.8%~102.5%,相对标准偏差为2.8%~6.6%。1,3,5-,1,2,4-和1,2,3-TCB的方法检出限分别为1.5 g/L,0.5 g/L和2.0 g/L。该方法与顶空、液液萃取和固相萃取法相比具有检出限低、富集因子高、重现性好、操作简便、干扰小等优点。采用本方法对5个实际海水样品中的TCBs进行了定量检测,结果表明其中两种样品含有2~3种待测物,浓度范围为1.9~6.7 g/L。

Determination of trichlorobenzenes in sea water by dispersive liquid-liquid microextraction-gas chromatography/mass method

Studies on the determination of trichlorobenzenes (TCBs) in sea water, by dispersive liquid-liquid microextraction (DLLME)-gas chromatography/mass (GC/MS) method, have been carried out. Parameters, such as the kind and volume of extraction solvent, disperser solvent, extraction time and temperature, were intensively studied and optimized. The result showed that the optimized DLLME condition was obtained when 0.5 mL of actone (disperser solvent), containing 10 L chlorobenze (extraction solvent) was used for the treatment of 10 mL synthetic seawater samples with 10 min-ultrasonic extaction at 25℃. Overall recoveries of the present method were 97.8%~102.5%with RSD values at 2.8%~6.6%. The detective limits for 1, 3, 5-, 1, 2, 4- and 1, 2, 3- TCB were 1.5 g/L, 0.5 g/L and 2.0 g/L, respectively. Comparing with traditional sample preparation procedures, e. g. head-space, liquid-liquid extraction and solid phase extraction, the present method was accurate, better enrichment property, better repeatability, easier to be operated with less interference. The present method has been applied for the determination of the TCBs residue concentration of 5 real samples. The result showed that two of them were found to contain 2~3 kinds of these TCBs. The TCBs detected in the studied samples were at concentration of(1.9~6.7)g/L.