离子色谱法测定高盐工业废水中含氟有机酸的含量

Determination of Fluorine-containing Organic Acids Content in High-salt Industrial Wastewater by Ion Chromatography

建立了可以同时测定高盐水体中三氟乙酸根、五氟丙酸根、七氟丁酸根含量的离子色谱法。样品以水作为溶剂稀释或溶解,采用IonPac AS23阴离子分离柱,使用HCO_(3)^(-)/CO_(3)^(2-)阴离子标准淋洗液,对淋洗液种类、淋洗液浓度、淋洗液内HCO_(3)^(-)/CO_(3)^(2-)比例、淋洗液流速以及抑制器电流进行讨论并确定了优化的色谱条件:淋洗液中HCO_(3)^(-)的浓度为0.8 mmol/L,CO_(3)^(2-)的浓度为4.5 mmol/L,淋洗液流速为1.0 mL/min,抑制器电流为30 mA。在此条件下,三氟乙酸根离子、五氟丙酸根离子、七氟丁酸根离子均达到基线分离。三氟乙酸根、五氟丙酸根离子、七氟丁酸根离子的检出限(信噪比为3)分别为0.0025 mg/L、0.0050 mg/L、0.0087 mg/L,线性相关系数R^(2)≥0.9975,相对标准偏差在0.86%~1.16%之间。该法简便、快速、灵敏度较高,为工业废水中含氟有机酸盐的含量检测提供一条可行的路径。

An ion chromatography method for simultaneous determination the content of trifluoroacetate,pentafluoropropionate and heptafluorobutyrate in high-salt wastewater was established.The sample was diluted or dissolved with water as a solvent,and the IonPac AS23 anion separation column and HCO_(3)^(-)/CO_(3)^(2-) anion standard eluent was used.The type of eluent,concentration of eluent,the ratio of HCO_(3)^(-)/CO_(3)^(2-) in the eluent,the flow rate of the eluent and the current of the suppressor were discussed and the optimized chromatographic conditions were determined.The concentration of HCO_(3)^(-) in the eluent was 0.8 mmol/L,the concentration of CO_(3)^(2-) was 4.5 mmol/L,the flow rate of the eluent was 1.0 mL/min,and the current of suppressor was 30 mA.Under these condition,the trifluoroacetate,pentafluoropropionate,and heptafluorobutyrate ions were all separated at baseline.The detection limits of trifluoroacetate,pentafluoropropionate,and heptafluorobutyrate ions (signal-to-noise ratio was 3) were 0.0025 mg/L,0.0050 mg/L,and 0.0087 mg/L,respectively.The linear correlation coefficient R^(2)≥0.9975,the relative standard deviation was between 0.86%and 1.16%.The method is simple,rapid and highly sensitive,and provides a feasible path for the content detection of fluorine-containing organic acid salts in industrial wastewater.