Preliminary study on a vapor generation technique for nickel without using carbon monoxide by inductively coupled plasma atomic emission spectrometry

The authors found that volatile nickel species could be generated by reaction in an aqueous solution with sodium or potassium borohydride under appropriate conditions at room temperature without using carbon monoxide. After vapor generation and gas–liquid separation, the volatile species was carried into an inductively coupled plasma (ICP) by argon gas, and the quantity of nickel determined by atomic emission spectrometry. The intensities of the Ni lines were strongly affected by the acidity of samples, the flow rate of argon carrier gas and the length of the transfer tube between the gas–liquid separator and ICP. A detection limit of 0.5 ng/ml and a precision of <5% was obtained under the following conditions: 0.12 M HCl acidified sample solution; 3% potassium borohydride solution with 0.5% potassium hydroxide added; sample uptake rate 2.8 ml/min; argon carrier gas flow 500 ml/min; and the length of the transfer tube kept as short as possible.