钼酸铵分光光度法测定总磷的改进

Improvement of Ammonium Molybdate Spectrophotometric Determination of Total Phosphorus

水体中的总磷含量是衡量水质的重要指标之一。但是国家标准GB11893-89推荐的过硫酸钾消解法在消解过程中易出现玻璃塞冲出的现象,使待测溶液的蒸发减少,因此经常导致消解失败。有鉴于此,文章改进了消解方法,采用聚四氟乙烯螺旋盖刻度管(后面简称螺旋盖刻度管)代替传统的玻璃具塞刻度管并通过实验,对曲线、空白检出限、准确度、精密度进行方法的有效性的评价。结果显示,改进后的总磷测定方法不影响结果的测定。且对人员的要求有一定的降低,可广泛应用于水质中总磷的监测。

The content of total phosphorus in water is one of the important indexes to measure water quality.However,the potassium persulfate digestion method recommended by the national standard GB11893-89 is prone to the phenomenon of glass plug flushing out in the digestion process,which reduces the evaporation of the solution to be tested,so it often leads to the failure of digestion.In view of this,this paper improves the digestion method,using the polytetrafluoroethylene spiral cover calibration tube(hereinafter referred to as the spiral cover calibration tube)instead of the traditional glass plug scale tube and passing the experiment.The effectiveness of the method was evaluated by curve,blank detection limit,accuracy and precision.The results showed that the improved method for the determination of total phosphorus did not affect the determination of total phosphorus.The requirements of personnel have been reduced to a certain extent,and can be widely used in the monitoring of total phosphorus in water quality.