中文摘要：

建立了反相离子对色谱（RPIPC）与电感耦合等离子体质谱（ICP—MS）联用技术快速分离测定水中痕量Cr（Ⅲ）和Cr（Ⅵ）的方法。通过考察流动相的pH值、离子对试剂及甲醇的浓度和EDTA的添加等对不同形态铬的保留时间及分离度的影响，确定当流动相组成为2．0mmol／LTBA，5％（V/V）甲醇，pH=5．5时，Cr（Ⅲ）与Cr（Ⅵ）可达最佳分离。ICP—MS测定时选用碰撞池技术以消除40Ar^12^＋与^35Cl^16OH^＋对^52Cr^＋的谱学干扰；进样100μL时，Cr（Ⅲ）与Cr（Ⅵ）的检出限分别为0．15μg／L和0．16μg／L。加标回收率在93．6％～106．2％之间；RSD〈4％（n=3）。以本方法分析了某市自来水、雨水及某品牌纯净水中Cr（Ⅲ）与Cr（Ⅵ）的含量，结果令人满意。

英文摘要：

A method was developed to simultaneously determine trace chromium species in water using ionpairing reversed phase chromatography （RPIPC）-inductively coupled plasma mass spectrometer （ICP-MS）. The chromatographic parameters were optimized to get the best separation, including the pH value of mobile phase, the concentrations of ion-pair reagent and methanol and the addition of EDTA in the mobile phase. The optimium mobile phase was 2.0 mmol/L tetrabutylammonium（TBA） , 5% methanol（v/v） , pH =5.5. Using collision cell technology to eliminate the mass interferences of 40Ar12C ＋ and 35 Cll6 OH ＋ in the analysis of 52 Cr＋ , and the detection limits of Cr（ Ⅲ ） and Cr（ Ⅳ ） were 0.15 μg/L and 0.16 μg/L for 100μL injections. The recovery range of spiked Cr（ Ⅲ ） and Cr（ Ⅳ） in water samples was 93.6% - 106.2% and the RSDs were less than 4% （n = 3 ）. The results were satisfying when analyzing the chromium speciation in drinking water and rain water using this method.