液液萃取-气相色谱法测定水质可萃取性石油烃C10～C40

摘要

建立了以环己烷为萃取剂、气相色谱法(氢火焰离子化检测器,FID)测定水质样品中可萃取性石油烃(C10～ C40)的分析方法.以正构烷烃混合标准溶液为定性和定量校准标准,以色谱峰面积总和与混合标准溶液总浓度建立校准曲线进行外标法定量.方法检出限为0.01 mg/L,经验证方法精密度和准确度良好.同时,分别以气相色谱法和红外光度法测定了地表水、污水处理厂出水、海水和化工废水等实际样品,对比实验结果表明,在可萃取性石油烃C10 ～C40的碳数范围内,气相色谱法的测试结果与红外光度法无明显差异,有较好的可比性.%A method of liquid-liquid extraction and gas chromatography (flame ionization detector,FID) analysis was developed for extractable petroleum hydrocarbons C10-C40 in water.N-alkanes were used as qualitative and quantitative standards and the standard curve was established between total peak area and total concentration for external standard quantification.The detection limit of petroleum C10-C40 was 0.01 mg/L.Precision and accuracy of the method were both satisfying.Analysis results were compared between gas chromatography and infrared spectrophotometry when determining petroleum in actual samples of surface water,effluent of municipal wastewater treatment plant,seawater and chemical industry wastewater.It was found that there was no significant difference between the results of EPH C10-C40 analyzed by GC-FID and infrared spectrophotometry.Results of two methods had good comparability.