微波催化显色反应分光光度法测定天然水中的磷

研究了用抗坏血酸作为还原剂磷钼蓝分光光度法测定磷时微波对于显色反应的催化作用和测定的适宜条件。试验表明:微波(高档,800W)可以使显色反应在3min内快速完成并稳定48h。线性范围:0~1.0mg/L,ε700nm=1.7×104L.mol-1.cm-1。对天然水样进行7次平行测定,其结果的RSD≤2.5%,回收率在98.6%~103%之间。与国家标准方法比较,无显著性差异。

Spectrophotometric determination of phosphate in natural waters by microwave catalytic chromogenic reaction

Study on microwave catalytic effect on chromogenic reaction of phosphomolybdic blue using ascorbic acid as a reducing reagent in spectrophotometric determination of phosphous was performed and proper conditions were evaluated as well. The experimental results showed that the chromogenic reaction was completed in 3 min and kept stable up to 48 h. Beers law was obeyed in the range of 01.0 mg/L. The molar absorptivity was _(700 nm)=1.710~4 Lmol~(-1)cm~(-1). The ralative standard deviation was no more than 2.5% and the recoveries were in the range of 98.63% by the determination of water samples(n=7). There was no significant difference between the proposed method and the national standard method.