Objective: To establish a method for the determination of sulfur dioxide (SO2) in the air of workplace, which including the process of collection by absorption in triethanolamine aqueous solution and the process of analysis and detection by iron chromatography directly without derivatization. Methods: SO2 in the air of workplace was collected at a flow rate of 0.5 L/min for 15 min through 10 ml of 3% triethanolamine aqueous solution filled in a porous glass plate absorption tube. The absorption solution passed through IonPacAS14A analytical column (4 mm×250 mm) and IonPacAG14 protective column (4 mm×50 mm) at a column temperature of 30 ℃, using Na2CO3 (3.0 mmol/L) -NaHCO3 (1.0 mmol/L) as mobile phase with the flow rate of 1.2 ml/min, and was detected by conductivity detector. Results: It showed that SO2 in triethanolamine solution could be stored for at least 7 d at room temperature (25 ℃) and 37 ℃. There was a linear relationship within the determination range of 0-8.00 μg/ml, the linear correlation coefficient was 0.9999. The sampling absorption efficiency was 98.1%-100.0%, the detection limit of the method was 0.018 μg/ml, the minimum detection concentration was 0.024 mg/m3 (based on V0=7.5 L) . The recovery rate was 99.22%-101.69%, the intra batch precision was 0.41%-1.34%, and the inter batch precision was 0.73%-1.77%. Conclusion: The method has the advantages of simple operation, high sensitivity and good accuracy. It can prevent SO2 from being oxidized and realize the direct detection of SO2 in the air of workplace without derivation.
目的： 建立三乙醇胺水溶液吸收采集、离子色谱无衍生检测工作场所空气中二氧化硫（SO2）的方法。 方法： 用多孔玻板吸收管盛装3%的三乙醇胺水溶液10 ml，以0.5 L/min流量采集工作场所空气中SO2 15 min，吸收液经IonPacAS14A分析柱（4 mm×250 mm）和IonPacAG14保护柱（4 mm×50 mm），在30 ℃柱温下，用Na2CO3（c=3.0 mmol/L）-NaHCO3（c=1.0 mmol/L）混合液为流动相，以1.2 ml/min的流速洗脱，电导检测器检测。 结果： SO2的三乙醇胺水溶液吸收样在室温（25 ℃）和37 ℃下至少可保存7 d，在0~8.00 μg/ml的测定范围内呈线性关系，相关系数为r=0.999 9，采样效率为98.1%~100.0%，方法的检出限为0.018 μg/ml，最低检出浓度为0.024 mg/m3（以V0=7.5L计），方法回收率为99.22%~101.69%，批内精密度为0.41%~1.36%，批间精密度为0.73%~1.77%。 结论： 该方法操作简单，灵敏度高，准确度好，可防止SO2被氧化，实现对工作场所空气中SO2的无衍生直接检测。.
Keywords: Ion chromatography; Non derivative detection; Occupational environment; Sulfur dioxide; Triethanolamine.