Determination of rare earth elements and other trace elements (Y, Mn, Co, Cr) in seawater using Tm addition and Mg(OH)2 co-precipitation

Nicolas Freslon (1, 2) , Germain Bayon (2) , Dominique Birot (2) , Claire Bollinger (1) , Jean-Alix J-A Barrat (1)

1 LDO - Domaines Océaniques
2 GM - Géosciences Marines

This paper reports on a novel procedure for determining trace element abundances (REE and Y, Cr, Mn, Co) in seawater by inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The procedure uses a combination of pre-concentration using co-precipitation onto magnesium hydroxides and addition of thulium spike. The validity of the method was assessed onto 25 ml volumes of certified reference materials (NASS- and CASS-4) and in house seawater standard. Procedural blanks were determined by applying the same procedure to aliquots of seawater previously depleted in trace elements by successive Mg(OH)2 co-precipitations, yielding estimated contributions to the studied samples better than 1.1% for all elements, with the exception of Cr (<3.3%) and Co (up to 8%). The reproducibility of the method over the six month duration of the study was smaller than 11% RSD for all the studied elements. Results obtained for NASS-5 and CASS-4 agree well with published working values for trace elements.

Keywords: Trace elements; Rare earth elements (REE); Seawater; Mg(OH)2 co-precipitation; ICP-MS; Thulium

Domains: Geochemistry; Global Changes

Nicolas Freslon, Germain Bayon, Dominique Birot, Claire Bollinger, Jean-Alix J-A Barrat. Determination of rare earth elements and other trace elements (Y, Mn, Co, Cr) in seawater using Tm addition and Mg(OH)2 co-precipitation. Talanta, 2011, 85 (1), pp.582-587. ⟨10.1016/j.talanta.2011.04.023⟩. ⟨insu-00617934⟩