利用连续流动分析仪快速测定碱熔法土壤全磷

根据 AA3 型连续流动分析仪（简称 CFA）测定磷的原理，研究了用 CFA 快速测定碱熔法待测液中土壤全磷 的方法。结果表明：通过优化 CFA 进样冲洗液及显色液的酸度，土壤全磷的标准曲线，在 0~8 mg/L 范围内呈线性相 关，相关系数 R2 达 1.000 0；全磷含量不同的 3 个土壤样品待测液 10 次重复测定结果变异系数≤2.0%；样品加标回收 率为 99.08%~102.42%；土壤成分分析标准物质 GBW07408 土壤全磷 CFA 法测定结果与其参考值一致，CFA 法与碱熔 钼锑抗手工比色法测定结果无显著差异。且由于 CFA 法去除了手工法中显色前样品酸度的调节步骤，因此 CFA 法具有 快速、准确测定碱熔法待测液中土壤全磷的效果。

Rapid Determination of Total Phosphorus in Soil by a Continuous Flow Analyzer

Based on a continuous flow analyzer (CFA, AA3 type) for the determination of phosphorus, the method of rapid determination of total phosphorus in soil by alkali fusion method with CFA was studied. By optimizing the acidity of the CFA sampler wash solution and color substrate solution, the results showed that the standard curve of soil total phosphorus determination by the CFA method was linear in the range of 0–8 mg/L, and the determination coefficient R2 was 1.000 0; the coefficient of variation of three soil samples with different total phosphorus content was less than 2%, and the recovery rate of sample addition was 99.08%–102.42%; the results of the total phosphorus of soil GBW07408 by the CFA method were consistent with the reference values. There was no significant difference between the CFA method and the traditional manual method. And because the CFA method had removed the step of adjusting the acidity of the sample before color rendering, the CFA method had the effect of rapid and accurate determination of total phosphorus in the solution by alkali melting method.