[MTT48-P02] Determination of picomolar of zirconium, hafnium, niobium and tantalum in seawater using chelating resin and subsequent ICP-MS determination
Keywords:Zr, Hf, Nb and Ta, high field strength elements, seawater
In this study, we developed a simple method to determine sub-picomolar to picomolar of dissolved Zr, Hf, Nb and Ta in seawater using chelating resin column preconcentration and ICP-MS. With mini-columns filled with commercially available chelating resin, HFSE were preconcentrated by 50 times. We obtained low blank values and good recovery enough to determine HFSE in open ocean surface waters. The detection limits, calculated from the procedural blank values, were 0.15 pmol/kg for Zr, 0.03 pmol/kg for Hf, 0.06 pmol/kg for Nb and 0.03 pmol/kg for Ta, respectively.
Using the new method, we revealed distributions of Zr, Hf, Nb and Ta in open ocean, the North Pacific Ocean, North Atlantic Ocean, Indian Ocean and in the marginal sea, Andaman Sea and Gulf of Thailand. We will discuss the fractionations of Zr–Hf and Nb–Ta in the marine environments.