Determination of rare earth elements in Fe-minerals using external calibration by LA-ICP-MS and application on Caue Iron Formation (Brazil)

TALANTA

卷:219

Article

Sousa, Denise V. M.^1,2  Abreu, Adriana T.¹  Sampaio, Geraldo M. S.¹  Lana, Cristiano C.¹  Rodrigues, Daniel A. S.¹  Nalini, Herminio A.¹ 

[1] Univ Fed Ouro Preto, Dept Geol, BR-35400000 Ouro Preto, MG, Brazil

[2] Univ Fed Minas Gerais, Dept Chem, BR-31270901 Belo Horizonte, MG, Brazil

关键词: REE plus Y;    Fe-(hydr)oxides;    Banded iron formations;    LA-ICP-MS;   

DOI  :  10.1016/j.talanta.2020.121239

来源: Elsevier

【 摘 要 】

The rare earth elements (REE) composition in Fe-mineral phases is an important tool in iron formation studies to obtain information about parent rocks and environmental and paragenetic processes. However, the determination of REE presents some difficulties, such as the low concentration of these elements, matrix complexity and lack of iron matrix certified reference materials. The aim of the present work is to propose an analytical method to determine the REE plus Y (REE + Y) contents at trace levels in Fe-(hydr)oxides by the laser ablation ICP-quadrupoleMS technique, using external calibration. The calibration curves were obtained from analyses of reference materials with different matrices, and the analytical conditions were checked on the NIST 614 glass. The linearity (R-2 >= 0.98), limit of detection (0.002-0.044 mu g g(-1)), limit of quantification (0.008-0.146 mu g g(-1)), recovery (88.4-112.4%), and intraday (0.1-14.1%) and interday (1.6-17.8%) precision were systematically assessed. The results obtained showed that the method is fit for the purpose and showed evidence of a non-significant interference of the matrix. Thus, the developed procedure was applied in the analyses of magnetite, martite, hematite, and goethite grains from Caue Iron Formation (Brazil). The REE + Y patterns of the minerals are consistent with the previous study of bulk analyses on whole rocks and highlight the postdepositional signature of these elements in banded iron formations.

【 授权许可】

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