IC-ICP-MS联用技术同时测定地表水中砷、铬、汞3种元素不同形态的含量

Simultaneous Determination of Different Forms of Arsenic,Chromium,and Mercury in Surface Water by Ion Chromatography with Inductively Coupled Plasma Mass Spectrometry

建立了离子色谱-电感耦合等离子体质谱联用技术同时测定地表水中砷、铬、汞等3种元素8种形态含量的方法。地表水样品用水相滤膜过滤,采用GIST C_(8)(250 mm×4.6 mm,5μm)色谱柱,以0.01 mol/L四丁基氢氧化铵+0.05%L-半胱氨酸+4%甲醇作为淋洗液(pH为6.0,流量为0.9 mL/min),分离样品后进行测定。试验结果表明:三价砷、二甲基砷、一甲基砷、五价砷、无机汞、甲基汞、乙基汞和六价铬可在10 min内得到有效分离,砷、铬、汞的检出限分别为0.075~0.15、0.86、0.00010~0.020μg/L,加标回收率分别为88.8%~108.3%、84.9%、87.7%~96.0%,相对标准偏差分别为1.41%~4.02%、1.82%、0.43%~2.17%。采用该方法检测地表水样品,可满足地表水标准限定值和检测要求。

A method is established for the simultaneous determination of eight forms of three elements,including arsenic,chromium,and mercury,in surface water using ion chromatography with inductively coupled plasma mass spectrometry.After filtering the surface water sample through a water phase filter membrane,a GIST C 8(250 mm×4.6 mm,5μm)chromatographic column is used,with 0.01 mol/L tetrabutylammonium hydroxide+0.05%L-cysteine+4%methanol as the eluent(pH 6.0,flow rate 0.9 mL/min).After separation,the sample is analyzed.The results show that trivalent arsenic,dimethyl arsenic,monomethyl arsenic,pentavalent arsenic,inorganic mercury,methylmercury,ethyl mercury,and hexavalent chromium can be effectively separated within 10 minutes.The detection limits for arsenic,chromium,and mercury are 0.075-0.15,0.86,0.00010-0.020μg/L,respectively,with spiked recovery rates of 88.8% to 108.3%,84.9%,87.7% to 96.0%,and relative standard deviations of 1.41% to 4.02%,1.82%,0.43% to 2.17%,respectively.Using this method to detect surface water samples can meet the standard limits and detection requirements for surface water.