一种水体及土壤/沉积物中直链烷基苯的前处理方法及GC-MS方法

A Pretreatment Method and GC-MS Method for Linear Alkylbenzene in Water and Soil/Sediment

建立了水体中及土壤/沉积物中直链烷基苯(LABs)的前处理和定量方法分析方法。水体样品经GF/F纤维膜过滤后,量取1.0 L的水样在分液漏斗中通过二氯甲烷(100 mL)液液萃取三次,合并萃取液。土壤/沉积物样品经自然风干后,称取10.0 g样品放在玻璃纤维滤膜上,包裹起来,放入自动索氏提取器的套筒内,在不锈钢量杯中加入80 mL二氯甲烷溶剂,沸腾60 min,淋洗60 min,溶剂回收10 min,完成提取,收集提取液。上述得到的水样萃取液和土壤/沉积物样品提取液均通过无水硫酸钠除去提取液中的水分,然后在旋转蒸发仪中浓缩至1 mL后,加入过量正己烷(10 mL),交换溶剂,并再次浓缩至1.0 mL,浓缩液通过内径为1.0 cm填充3.0 g硅胶(100~200目)及0.5 g无水硫酸钠的层析柱,并加入25 mL正己烷淋洗,收集淋洗液后,浓缩并定容至1.0 mL,通过气相色谱–质谱(GC-MS)选择离子外标法定量。

A method of pretreatment and quantitative analysis of linear alkylbenzenes (LABs) in water and soil sediments was developed. Water samples were filtered by GF/F fiber membrane, the 1.0 L fil-tered water sample was extracted three times by dichloromethane (100 mL) in a separatory funnel, and then the extraction fluid was combined. After the soil sediment sample is naturally air dried, place 10.0 g sample on the fiberglass membrane, wrap it and place it in the sleeve of the Soxhlet extractor. Add 80 mL dichloromethane to a stainless steel measuring cup. After it boils for 60 minutes, wash it for 60 minutes. Then after we recycle the solvent for 10 minutes, the extraction is completed. The extract can be collected. Both the obtained water sample extract and the soil sediment sample extract are removed water by anhydrous sodium sulfate. The solution was then concentrated to 1 mL in Rotary evaporator, then an excess of 10 mL of n-hexane was added, the solvent was exchanged, and the concentration was again reduced to 1.0 mL, the concentrated solution was filled with 3.0 g Silica Gel (100~200 Mesh) and 0.5 g anhydrous sodium sulfate through a column with an internal diameter of 1.0 cm, and 25 mL n-hexane was added to the column. After collecting the eluent, it was concentrated and fixed to 1.0 mL;ion external standard method was selected and quantified by gas chromatography-mass spectrometry (GC-MS).