采用电感耦合等离子体质谱法（ICP-MS）测定了钒钛磁铁矿中12种杂质元素（砷、铅、锡、锑、锆、铋、锌、铜、钴、镍、铬及钼）,用微波消解法以氢氟酸及硝酸作为溶解酸,有效地解决了因样品中含有较高量的二氧化钛、二氧化硅、五氧化二钒及三氧化二铝而造成的溶样困难问题。通过用高纯物质按65%铁,20%二氧化钛和10%五氧化二钒的配比制成的混合物,按相同方法消解处理成为基体空白溶液,检测作为扣除空白并选择适宜的同位素作为测定各元素的分析同位素,从而解决可能存在的质谱干扰。此外,加入铑溶液作内标克服了基体效应的干扰。12种元素的检出限（3s/k）在0.11～1.92μg.L-1范围内。各元素测定值的相对标准偏差（n=8）均小于5%。应用此方法分析了4个国家标准物质,所得测定结果与认定值相符。同时用此方法与电感耦合等离子体原子发射光谱法分析了3个磁铁矿样品,2种方法所测得的12种元素的结果相互符合。%Twelve impurity elements,including As,Pb,Sn,Sb,Zr,Bi,Zn,Cu,Co,Ni,Cr and Mo,in vanadium and titanium bearing magnetite were determined by ICP-MS.Microwave assisted sample digestion with HF and HNO3 was shown to be very effective for dissolution the magnetite sample with high contents of TiO2,SiO2,V2O5 and Al2O3.Mass spectral interferences were eliminated by preparation of matrix blank solution with high purity iron,titanium and vanadium（65% Fe＋20% TiO2＋10% V2O5）,and by selection of appropriate istopes for each of the analyte elements.Interference due to matrix effect was overcome by addition of rhodium solution as internal standard.Values of detection limit（3s/k） for the 12 elements were found in the range of 0.11 to 1.92 μg·L-1.Precision was tested by analyzing a same magnetite sample for 8 determinations,values of RSD′s calculated were all less than 5%.As shown by the results obtained by analyzing 4 CMR′s with the present method,good consistency with certified values was attained.In addition,the results of the 12 elements in V-Ti magnetite sample determined by this method were found to check quite well with the results found by ICP-AES.
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