一种提高油样中低含量石油磺酸盐分析效率的方法

A method of improving analytical efficiency of petroleum sulfonate with low content in oil samples

关键词:  石油磺酸盐  溶剂萃取  液相色谱  含量分析  回收率

Key words:  petroleum sulfonates  solvent extraction  liquid chromatography  content analysis  recovery

摘要:

为了准确分析油田化学驱采出液油样中石油磺酸盐的含量,介绍了一种在油样中加入不同极性溶剂组成的萃取体系的预处理技术,将石油磺酸盐萃取到水相,利用液相色谱仪对其进行检测的方法。取适量油样,依次加入正己烷、二氯甲烷、无水乙醇和蒸馏水,振荡均匀后静置分层,取下层水相溶液进行色谱分析。色谱柱为阴离子交换柱,流动相为甲醇/水和甲醇/盐水(含0.2 mol/L乙酸和0.2 mol/L乙酸铵),梯度洗脱。实验结果表明,该预处理技术联合液相色谱法检测技术分析效率较高,加标回收率高于90%,液相色谱最小定量限10 mg/L,线性范围10~2000 mg/L。该方法可对油样中低含量的石油磺酸盐进行快速定量分析。

Abstract:

A liquid chromatographic method combined with sample pretreatment technology has been developed to accurately determinate the concentration of petroleum sulfonates in oil samples of oilfield produced liquid. Petroleum sulfonates were extracted from oil phase into water phase with several different polar solvents, and the water phase solution was detected by liquid chromatography. The suitable amount oil samples were weighed into the test tube, and n-hexane, dichloromethane, ethanol and distilled water were added in turn. The test tube was shaken thoroughly and stayed for layering. The lower layer solution was used for chromatographic analysis. The anionic exchange column and gradient elution including methanol/water and methanol/saline were used. The results showed that the adopted extraction technology had a high recovery over 90%, and the limit of quantitation and linear range of chromatographic method were 10 mg/L and 10-2000 mg/L, respectively. The developed method herein can be used to analyze the petroleum sulfonates with lower content of in oil samples rapidly and accurately.