土壤中铅的测定方法研究

Determination of lead in soil

目的对土壤中铅的测定方法进行改进。方法采用一次性加入足量混合酸的方法,即加入7 ml硝酸、5ml氢氟酸、2 ml高氯酸对土壤样品进行消化;再找到最佳的仪器条件:波长283.30 nm、灯电流5 mA、狭缝0.20 nm来测定样品。结果新方法的线性范围为0～150μg/L,相关系数r=0.999 4,RSD为0.27%～1.33%,回收率为95.1%～104.1%。标样测定结果经t检验,t=0.207,P>0.05,与国标方法差异无统计学意义(t<t(0.05,10)=2.228)。结论该方法准确度、精密度良好,是一种简便、可行的测定方法。

Objective To improve the method for determination of lead in soil. Methods Soil samples were digested by mixed acid including 7 ml nitric acid, 5 ml hydrofluoric acid, and 2 ml perchloric acid. The best instrument condition was the wave length of 283.30 nm, lamp current of 5 mA, slit width of 0.20 nm. Results The linear range of the new method was 0 - 150 μg/L, the correlation coefficient was 0. 999 4, RSD was 0. 27% - 1.33% , the recovery rate was 95.1% - 104. 1%. There was no significant difference between the new method and national method （ t = 0. 207, P 〉 0. 05 ） . Conclusion The method is accuracy and good precision.