冷蒸气原子吸收光谱法测定接装纸中的Hg

Determination of Hg in Tipping Paper with Cold Vapor Atomic Absorption Spectrometry

为建立微波消解-冷蒸气原子吸收光谱法测定接装纸中Hg含量的方法,考察了微波消解、盐酸(反应介质)浓度、硼氢化钠(还原剂)浓度和载气流速等测定条件对测定结果的影响,并采用该方法测定16个国产接装纸样品中的Hg含量。结果表明:①采用HNO3-HCl-H2O2-HF体系微波消解样品,样品消解完全;②Hg测定的最佳反应条件为硼氢化钠浓度0.3%(质量分数),载液中盐酸浓度5%(体积分数),载气流速为95mL/min;③Hg的检出限为0.016μg/L,重复性RSD≤3.0%,回收率为90.0%～98.0%;④16个接装纸样品中的Hg含量均低于0.6mg/kg,其中有2个样品未检出,含量为0～0.1mg/kg的样品有6个,含量为0.1～0.5mg/kg的样品有7个,含量为0.599mg/kg的样品只有1个。

A method for determining mercury （Hg） in tipping paper with microwave digestion-cold vapor atomic absorption spectrometry was developed, the influencing factors, such as microwave digestion, HCI （reaction medium） concentration, NaBH4 （reducing agent） concentration and carrier gas flow rate, etc. were investigated, and the contents of Hg in 16 domestic tipping paper samples were determined with the established method. The results showed that： 1 ） the samples were completely digested under microwave in HNO3- HCl- H2O2 -HF mixture solution; 2） the optimum conditions for determining Hg were： the HCI concentration in carrier solution 5% （v/v）, NaBH4 concentration 0.3% （m/v） and the flow rate of carrier gas 95 mL/min; 3） the recoveries of Hg was from 90.0% to 98.0 % with RSDs of ≤ 3.0% and limit of detection of 0.016 μg/L; 4） the Hg content in no sample was higher than 0.6 mg/kg, in 6 samples was from 0 to 0.1 mg/kg, 7 samples from 0.1 to 0.5 mg/kg, 1 sample 0. 599 mg/kg, and 2 samples not detectable.