Determination of Cr in soil by microwave digestion with inductively coupled plasma mass spectrometer

To establish a method for determine and analyze Cr in soil,the samples are digested by closed-vessel microwave and directly analyzed with ICP-MS.After microwave digestion in HNO3-HCl-HF mixed system,the samples are determined by ICP-MS.The internal standard elements In is used to compensate for matrix suppression effect and sensitivity drift.Meanwhile,the national standard reference material GBW07439 is determined and analyzed to verify the accuracy of this method.The results are shown as follows:less than 0.01 ng/g of the detection limits,over 0.9998 of the correlative coefficient of the calibration curves,lower than 2.5% of RSD,93.0%-105.3% of the recovery rates of Cr in certified reference material.This method is convenient,accurate and applied to determine various trace elements in soil samples.