静态顶空-气相色谱法测定土壤中甲基叔丁基醚

Determination of Methyl Tertiary Butyl Ether (MTBE) in Soil by Static Headspace Gas Chromatography

建立了以水作为浸提剂、室温下浸提40min、浸提液在90℃下顶空平衡30min的静态顶空-气相色谱-火焰离子化检测器测定土壤中甲基叔丁基醚(MTBE)的方法,并对提取条件、顶空条件等进行了优化。结果表明:土壤中MTBE质量分数低于0 370mg kg时,采用固液比1∶5浸提土壤,MTBE添加质量分数为0 037mg kg时,方法回收率为72%～74%,RSD为4 4%～7 5%;土壤中MTBE质量分数高于0 370mg kg时,采用固液比1∶10浸提土壤,添加质量分数为0 740mg kg时,2次浸提后方法回收率为98%～105%,RSD为2 4%～5 2%。方法检出限为1 85μg kg。

<Abstrcat> A method for the determination of methyl tertiary butyl ether (MTBE) in soil has been developed. The soil was extracted by water and the extract was put into headspace bottle for 30 min at 90℃, and detected by GC/FID, manual inject. The extraction and headspace conditions were optimized. When the concentration of MTBE in soil was lower than 0.370 mg/kg, the soil was extracted with the solid to liquid ratio(S∶L) 1∶5, the relative standard deviations(RSD) and the recoveries were 4.4%～7.5% and 72%～74% at the 0.037 mg/kg added standard concentration level. When the concentration of MTBE in soil was higher than 0.370 mg/kg,the S∶L was 1∶10, the RSD and the recoveries after extracted twice were 2.4%～5.2% and 98%～105% at the 0.740 mg/kg added standard concentration level. The method detection limits(MDLs) were 1.85 μg/kg.This method was simple and efficient. It has been applied to the determination of MTBE in black soil from gas station.