Determination of Trace Zirconium in Granodiorite by Inductively Coupled Plasma-Mass Spectrometry with Sealed Acid Digestion at High Pressure

Determination of trace elements in rocks by Inductively Coupled Plasma-Mass Spectrometry with sealed acid digestion at high pressure is widely used in geological analysis.Zirconium occurs as insoluble accessory minerals such as zircon and rutile in granodiorite, so the recovery of zirconium is always low.This study adds the pretreatment process of removing silicon, increasing the amount of hydrofluoric acid and introducing fluoride ions in the solution to form zirconium fluorine complex ions which improves the stability of zirconium.These steps improve the recovery of zirconium(up to 95%) and achieve an accurate determination of trace zirconium in granodiorite.The precision of this method is less than 5%(RSD, n=11) and the detection limit is 0.052μg/g.Zirconium content of granodiorite in the Karamay area is determined by this method, which is consistent with the results determined by the alkaline fusion of Na₂O₂, LiBO₂ and XRF method.Furthermore, this method has a small matrix effect and low detection limit, which can analyze various trace elements(Li, Be, Sc, for example) simultaneously.