铋磷钼蓝分光光度法快速测定钒氮合金中磷量

Bismuth phosphomolybdate blue spectrophotometric method for the rapid determination of phosphorus in vanadium-nitrogen alloy

提出一种快速而简单的分光光度法测定钒氮合金中微量磷。讨论了试料量、显色条件对显色反应的影响,确定了最佳试验条件。试样经硝酸(1+1)溶解并将磷氧化成高价后,在0.9～1.0mol/L硝酸介质中,以铋磷钼蓝分光光度法测定,基体钒对测定有影响,可不经预先分离,在绘制校准曲线的标准溶液中加入与样品中相同含量的钒克服。测定结果相对标准偏差(n=8)小于5%,加标回收率在99.5%～100.6%。该法能满足钒氮合金的测定要求,而且特别适合于炉前快速分析。

A rapid and simple method for the determination of micro phosphorus in vanadium-nitrogen alloy by spectrophotometry was proposed. The effects of sample dosage and coloring conditions on the color reaction were discussed, and the optimum experimental conditions were obtained. The sample was decomposed with HNO3 （1＋1）. The phosphorus was oxidized to high valence, and then its content was determined by bismuth phosphomolybdate blue spectrophotometric method in 0. 9--1.0 mol/L HNOa medium. The matrix vanadium had certain interference with the determination, but it could be avoided by adding the same amount of vanadium into the standard solution in plotting the calibration curve without pre-separation. The RSDs （n=8） of determination results were less than 5.0G, and the recoveries rate were 99.5 %--100.6 %. This method totally satisfied the analytical requirements of vanadium-nitrogen alloy, and was especially suitable for the rapid on-the-spot sample analysis.