肥料中重金属元素镍含量测定方法的研究

Study on the methods for measuring nickel content in fertilizers

肥料中镍的测定缺少相应的标准方法,选择水溶肥料、复混肥料、有机肥料、土壤调理剂4类肥料样品,研究王水消解,其中消解液中镍采用火焰原子吸收光谱法(FAAS)、电感耦合等离子体发射光谱法(ICP-OES)、电感耦合等离子体质谱法(ICP-MS)3种方法测定,探讨肥料中的镍含量测定方法。结果表明:3种方法检出限:FAAS>ICP-OES>ICP-MS,分别为0.11 mg/L、0.02 mg/L和3.94μg/L。3种方法测定结果相对标准偏差(RSD,n=6)在1.59%~13.59%之间,加标回收率为80%~118%。相关性分析结果发现,FAAS和ICP-OES的测定结果之间的相关系数R^(2)=0.9678,ICP-OES和ICP-MS测定数据间相关系数R^(2)=0.9801,FAAS和ICP-MS之间相关系数R^(2)=0.9649,均呈良好的线性相关关系,且3种方法测定结果差异不明显。通过研究得出建立肥料中镍的测定方法,采用王水-电热板消解肥料样品,待测液中的镍元素含量可用FAAS、ICP-OES、ICP-MS测定,实验室根据实际情况可选择使用不同的检测方法。

There is still a lack of corresponding standard methods for the determination of nickel in fertilizers,using flame atomic absorption spectrometry(FAAS),inductively coupled plasma emission spectrometry(ICP-OES),and inductively coupled plasma mass spectrometry(ICP-MS)to determine the nickel content in fertilizers.In the experiment,four types of fertilizer samples,water-soluble fertilizer,compound fertilizer,organic fertilizer,and soil conditioner were selected,and the same pre-treatment method of aqua regia digestion was adopted,and the digestion solution was tested separately.The test results show that the detection limits of the three methods are:FAAS>ICP-OES>ICP-MS,which were 0.11 mg/L,0.02 mg/L and 3.94μg/L,respectively,the relative standard deviation(RSD,n=6)of the determination results is between 1.59%~13.59%,and the recovery rate is 80%~118%.Correlation analysis results show that the correlation coefficient between the data measured by FAAS and ICP-OES is 0.9678,the correlation coefficient between the data measured by ICP-OES and ICP-MS is 0.9801,and the correlation coefficient between the data measured by FAAS and ICPMS is 0.9649,which is a linear relationship.The test results show that there is little difference in the determination results of the three methods.The method for the determination of nickel in fertilizers was established through the research.The fertilizer samples were digested with aqua regia-electric hot plate.The content of nickel in the liquid can be determined by FAAS,ICP-OES and ICP-MS.The laboratoy can choose to use different detection methods according to the actual situation.