两种消解法测定沉积物总磷的对比

Comparison of Two Kinds of Digestion Method for the Determination of Total Phosphorus in Sediment

通过过硫酸钾消解法与HClO4-H2SO4消解法对土壤和水系沉积物的标准物质,以及三峡水库沉积物未知样品中的总磷含量进行测定,并对检测结果进行对比,分析过硫酸钾消解法测定沉积物总磷的可行性。结果表明,在标准样品中,HClO4-H2SO4消解法的检测结果是标准值的83%～100%,并且所有结果均在其不确定度范围之内;过硫酸钾消解法的检测结果仅达到标准值的19%～42%,超出其不确定度范围,不能作为有效数据。在未知样品中,过硫酸钾消解法检测结果也远低于HClO4-H2SO4消解法检测结果,只达到后者的32%～52%。由此可见,过硫酸钾消解法测定沉积物或土壤中总磷,仍需要进一步的研究,以达到符合实际的检测结果。

Using potassium persulfate digestion method and HClO4-H2SO4 digestion method to test the content of total phosphorus of standard substances in soil and stream sediment and unknown samples of sediment in Three Gorge reservoir,and then compare the test results and analysis the feasibility of potassium persulfate digestion method.The results show that： for the standard sample,the test results of HClO4-H2SO4 digestion is 83 to 100 % of the standard value and all results were within the scope of its uncertainty;the test results of potassium persulfate digestion only up to 19 % to 42 % of standard value,and exceeding the uncertainty range,can not serve as valid data.For the unknown samples,the test results of persulfate digestion method is much lower than HClO4-H2SO4 digestion test results,which only reached 32 % to 52 %.Thus,the potassium persulfate digestion method for the determination in sediment or soil TP,still need further research in order to close to the true value.