气相色谱-质谱法测量有机溶剂的水分含量

Determination of Water Content of Organic Solvents by GC-MS

水分是有机溶剂的主要杂质之一,需要快速准确的测定,以保证产品质量合格。采用气相色谱-质谱仪（GC-MS）测量11种有机溶剂中的水分含量。采用重量法配制水的辛醇标准溶液来校准GC-MS,使得水分含量溯源到纯水质量的SI单位;采用标准加入法测定空白辛醇的水分含量,使GC-MS成为一种完全独立的水分测量方法。11种有机溶剂的水分含量在200～3 300 mg/kg范围内,测量结果的相对标准偏差在0.6%～22%范围内,测量方法的检出限为85 mg/kg。水分含量在160～1 500 mg/kg范围内的8种有机溶剂,相对误差在-8.5%～27%范围内,准确度较好。该方法适用于中低水分含量的有机溶剂的测量,可以广泛应用在水分快速筛查和生产工艺控制等领域。

Water content,one of main impurities in organic solvents,should be determined accurately and fastly for the assurance of the quality.In this work,gas chromatography-mass spectrometry（ GC-MS） was employed to measure 11 organic solvents.Homemade water standard of water in octanol prepared by the gravimetry were used to calibrate GC-MS,which makes the water content result traceable to SI unit. The water content of the blank octanol was calculated based on the standard addition method,which makes GC-MS independent from other methods.The measured water contents ranged from 200 to 3 300 mg/kg and the standard deviation ranged from 0. 6% to 22%. Limit of detection（ LOD） of GC-MS is 85 mg/kg. Eight kinds organic solvents with water contents ranging from 160 to 1 500 mg/kg have the relative errors ranging from -8. 5% to 27%. This new method is suitable for the measurement of organic solvents and can be applied in the screening of product and the control of production.