Simultaneous determinations of zirconium, hafnium, yttrium and lanthanides in seawater according to a co-precipitation technique onto iron-hydroxide

摘要

Very low concentrations (pg mL 1 or sub-pg mL 1 level) along with the high salinity are the mainudproblems in determining trace metal contents in seawater. This problem is mainly considered forudinvestigations of naturally occurring YLOID (Y and Lanthanides) and Zr and Hf in order to provide preciseudand accurate results. The inductively coupled plasma mass spectrometry (ICP-MS), both in high and lowudresolution, offers many advantages including simultaneous analyses of all elements and their quantitativeuddetermination with detection limits of the order of pg mL 1. However in the analysis of YLOID inudseawater, a better determination needs an efficient combination of ICP-MS measurement with a preconcentrationudtechnique. To perform an ultra-trace analysis in seawater, we have validated an analyticaludprocedure involving an improved modified co-precipitation on iron hydroxides to ensure the simultaneousudquantitative recovery of YLOID, Zr and Hf contents with measurement by a quadrupole ICP-MS.udThe validity of the method was assessed through a series of co-precipitation experiments andudestimation of several quality control parameters for method validation, namely working range and itsudlinearity, detection limit, quantification limit, precision and spike recoveries, and the methodologicaludblank choice, are introduced, evaluated and discussed. Analysis of NASS-6, is the first report on the latestudseawater reference material for YLOID, hafnium and zirconium.