油田水中新型水驱示踪剂氟苯甲酸的气相色谱-质谱分析

Study on Determination of 2-Fluorobenzioc Acid in Oilfield Brain for Waterflood Tracing by Gas Chromatography-Mass Spectrometry

建立了油田水中新型水驱示踪剂 2 -( 2 -FBA)的痕量分析方法。该方法将过滤、固相萃取、衍生等样品前处理技术有效地结合在一起 ,应用气相色谱 -质谱 ( GC/ MS)技术对其进行定性和定量测定。结果表明 :方法具有较高的灵敏度和可靠的不确定度 ,油田水取样量为 2 5 0 m L时 ,2 -FBA最低检测限达 4ng/ L。 40 0 ng/ L2 -FBA的单次测量结果扩展不确定度为 5 0 ng/ L,即相对扩展不确定度优于 1 4%。本方法采用 4-甲基 -氟苯甲酸 ( 4 -TMFBA)作为内标物质校正衍生及测量过程。2 -FBA的浓度为 5～ 2 0 0 0 ng/ L,标准曲线的相关系数>0 .9998。此方法适用于油田、环境、生物、药物等样品中痕量 2 -FBA的快速、准确分析。

A method of ultra-trace measurement of 2-FBA in oilfield brine is established using SPE enrichment & separation solid-phase in combination with gas chromatography- mass spectrometry (GC/MS). The method described here is rapid, accurate, and reliable for ultra-trace determination of 2-FBA in oilfield brine. The lowest detection limit of 2-FBA is 4×10 -9g/L when the 250mL sample was analyzed and the typical relative standard deviation of measurement is 10% by this method. The expanded uncertainty of a once measurement for 400ng/mL is 50 ng/mL, that means the relative uncertainty is better than 14%. The 4-methyl -fluorobenzoic (4-TMFBA) acid is used as the internal standard to modify the derivation procedure and determination by GC/MS. The range of calibration curve in the measurement by GC/MS was estimated from 5 to 2000ng/mL (R 2≥0.999 8) with internal standard calibration. It can be used in analysis of 2-FBA in other samples such as environ-mental, biological and drug samples. The work makes also the base for analysis of other FBAs in oilfield brine when used as waterflood tracers in future.