大体积直接进样离子色谱法测定饮用水中9种卤代乙酸和6种阴离子

Determination of Nine Haloacetic Acids and Six Anions in Drinking Water by Ion Chromatography with Large Volume Direct Injection

建立了一种采用大体积直接进样离子色谱测定饮用水中9种卤代乙酸和6种阴离子的新方法。采用高容量的IonPacAS9HC阴离子色谱柱,在进样量为500μL时,以28mmol/LNa2CO3为淋洗液,采用流速梯度洗脱,可在35min内同时测定上述15种被测物。对9种卤代乙酸的检测限为1 91～49 98μg/L,其中对二氯乙酸、三氯乙酸的检测限分别为4 62和5 11μg/L。应用该方法对北京市9个自来水厂的源水及出厂水中的卤代乙酸进行了测定。结果表明,所测水样中仅含有二氯乙酸和三氯乙酸,其他卤代乙酸均未检出。

A novel method was developed for the simultaneous determination of nine haloacetic acids (HAAs) (mono, di, trichloroacetic acids; mono, di, tribromoacetic acids; bromochloroacetic acid, dibromochloroacetic acid, and bromodichloroacetic acid) and six anions (fluoride, chloride, nitrite, nitrate, phosphate and sulfate) in drinking water by ion chromatography with large volume direct injection. With a high capacity anion exchange column, IonPac AS9HC column, and 28 mmol/L sodium carbonate as eluent, the nine HAAs as well as fluoride, chloride, nitrite, nitrate, phosphate and sulfate could be well separated and determined within 35 min by employing a flow rate gradient. A 500 μL sample loop was used. The detection limits for the nine HAAs were between 191 and 4998 μg/L. The spiked recoveries for the nine HAAs were between 91% and 1125%. The method was applied for the determination of the haloacetic acids in the source waters and treated drinking waters from nine waterworks of Beijing. The results indicated that there were only little dichloroacetic acid and trichloroacetic acid in the water.