电感耦合等离子体原子发射光谱法测定土壤中8种组分

为满足土地质量调查的需求,实现土壤中多组分的同时消解及准确测定,提高大批量样品的分析效率,建立了土壤样品经高压密闭消解后,采用电感耦合等离子体原子发射光谱法(ICP-AES)测定K₂O、Na₂O、CaO、MgO、Ba、Mn、Cu、Zn的方法。通过对消解体系、酸用量、消解温度等方面的考察,确定最佳实验条件;并对待测液中共存元素Al、Fe的干扰进行探讨,两者均不干扰测定。各组分校准曲线线性相关系数均大于0.999;检出限为0.01~10μg/g。实验方法用于测定土壤标准样品GBW07385、GBW07386、GBW07388中K₂O、Na₂O、CaO、MgO、Ba、Mn、Cu、Zn,测定结果的相对标准偏差(RSD,n=12)为1.1%~4.3%,相对误差RE为-4.0%~4.6%。采用实验方法对土壤实际样品中K₂O、Na₂O、CaO、MgO、Ba、Mn、Cu、Zn进行测定,结果的RSD(n=6)为1.2%~4.6%;并与地矿行业标准方法DZ/T 0279.2—2016测定结果进行比对,测得结果基本一致。

Determination of eight components in soil by inductively coupled plasma atomic emission spectrometry

In order to meet the requirements of land quality investigation, to realize the simultaneous digestion and accurate determination of multi-components in soil, and to improve the analytical efficiency of large quantities of samples, a method for simultaneous determination of K₂O, Na₂O, CaO, MgO, Ba, Mn, Cu and Zn in soil sample by inductively coupled plasma atomic emission spectrometry (ICP-AES) after high-pressure digestion in closed system was established in this study. The digestion system, the acid dosage and the digestion temperature were investigated to obtain the optimum experimental conditions. The interference of the coexisting elements in testing solution including Al and Fe was discussed. The results showed that both two elements had no interference with the determination. The linear correlation coefficients of calibration curves of elements were all greater than 0.999. The detection limits of method were between 0.01μg/g and 10μg/g. The proposed method was applied for the determination of K₂O, Na₂O, CaO, MgO, Ba, Mn, Cu and Zn in certified reference materials of soil (GBW07385, GBW07386 and GBW07388). The relative standard deviations (RSD, n=12) of results were between 1.1% and 4.3%, and the relative errors (RE) were between -4.0% and 4.6%. The contents of K₂O, Na₂O, CaO, MgO, Ba, Mn, Cu and Zn in actual soil sample were determined according to the experimental method, and the RSD (n=6) were between 1.2% and 4.6%. The measured results were compared and consistent with those obtained by standard method of mineral industry (DZ/T0279.2-2016).