论文部分内容阅读
建立了反相离子对色谱-电感耦合等离子体-质谱(RPIC/ICP-MS)联用技术测定水中痕量三价铬Cr(Ⅲ)和六价铬Cr(Ⅵ)的分析方法。通过对流动相的组成、浓度、pH值等色谱条件的实验,确定当流动相组成为0.25mmol.L-1乙二胺四乙酸二钠和2mmol.L-1四丁基氢氧化铵,5%(V/V)甲醇,pH=7.0时,成功分离了Cr(Ⅲ)和Cr(Ⅵ)离子。ICP-MS测定时选用碰撞反应接口技术(CRI)消除40Ar12C+与35Cl16OH+对52Cr+的质谱干扰,Cr(Ⅲ)和Cr(Ⅵ)的检出限分别为0.50、0.34μg.L-1,RSD<10%(n=5)。应用于湖北黄冈、黄石、襄阳等地企业废水中Cr(Ⅲ)和Cr(Ⅵ)含量的测定,加标回收率为86.1%—100.1%。与分光光度法比对,实验证明本方法能克服用分光光度法测定水中六价铬由样品本身带来的干扰。
An analytical method was developed for the determination of trace Cr (Ⅲ) and Cr (Ⅵ) in water by RP-ICP-MS. The mobile phase consisted of 0.25 mmol.L-1 disodium ethylenediaminetetraacetate and 2 mmol.L-1 tetrabutylammonium hydroxide, and 5% ( V / V) methanol, pH = 7.0, Cr (Ⅲ) and Cr (Ⅵ) ions were successfully separated. The detection limits of Cr (Ⅲ) and Cr (Ⅵ) for Cr (Ⅲ) and Cr (Ⅵ) were 0.50,0.34μg.L-1 and RSD <10 by using collision reaction interface technology (CRI) to eliminate the interference of 40Ar12C + and 35Cl16OH + % (n = 5). The method was applied to the determination of Cr (Ⅲ) and Cr (Ⅵ) in wastewater from enterprises in Huanggang, Huangshi and Xiangyang of Hubei Province. The recoveries were in the range of 86.1% -100.1%. Compared with spectrophotometry, experiments show that this method can overcome the spectrophotometric determination of hexavalent chromium in water by the sample itself.