氧弹燃烧–离子色谱法测定污泥可燃组分中的全硫

Determination of total sulfur in incineration sludge by oxygen bomb combustion–ion chromatography

建立氧弹燃烧–离子色谱法测定污泥可燃组分中全硫含量。采用无水乙醇为助燃剂处理样品,用纯水作为吸收液进行吸收,吸收时间为30 min,然后用离子色谱法测定。以KOH溶液梯度洗脱,流量为1.0 mL/min,柱温为30℃时,硫酸根与其它常见阴离子可完全分离。硫酸根质量浓度x在0.20~10.0 mg/L范围内与色谱峰面积y线性良好,线性方程为y=3.9608x+0.1947,相关系数为0.9995。该法应用于污泥可燃组分的全硫测定,方法检出限为0.18 mg/kg,平行测定值的相对标准偏差为2.12%~3.05%(n=6),加标回收率为85.6%~92.5%。该法选择性好,检出限低,有利于低浓度样品的测定。

A new method for the determination of total sulfur in incineration sludge by oxygen bomb combustion–ion chromatography was developed.Samples were pretreated by anhydrous ethanol as combustion supporting agent,pure water was used as absorption for 30 min,and then determined by ion chromatography.KOH solution gradient elution was used with the flow rate of 1.0 mL/min,and the column temperature was 30℃.Under this condition,sulfate could be completely separated from other common anions.The mass concentration of sulfate had good linear relationship with the chromatographic peak area in the range of 0.20–10.0 mg/L,the linear equation was y=3.9608x+0.1947 with the corelation coefficient of 0.9995.The method was applied to the determination of total sulfur in incineration sludge,the detection limit was 0.18 mg/kg,and the relative standard deviations of parallel determinations were 2.12%–3.05%(n=6),the recoveries were 85.6%–92.5%.The method has high selectivity with low detection limit,which is beneficial to the determination of low concentration samples.