三种总氮总磷联合消解液测定效果的比较

A comparison of performances of three reagents for total Nitrogen and Phosphorus simultaneous digestion

在同一试验条件下对三种总氮总磷联合消解液的基本参数（空白值、检出限、精密度和耗药量）、标准物质的回收率和不同自然水样的分析等方面进行了比较。三种联合消解液的标准物质加标回收率均比较高，总氮，总磷标准物质的回收率范围分别为97．2％～101．3％和95．8％～100．8％；利用三种联合消解液消解测定22个自然水样中总氮、总磷的结果均与国家标准方法相近（P〉0．05）。三种联合消解方法可以替代国家标准方法测定水体的总氮、总磷浓度，满足单个水样消解一次完成总氮总磷的连续测定，节省药品、简化操作。但在测定氮、磷含量较高的水体时，消解液一和消解液二分别存在总磷、总氮结果偏低的可能。

A comparison of three simultaneous digestion reagents for the determination of total nitrogen and total phosphorus in surface water was conducted. Three digestion reagents were evaluated by standard parameters （ blank, detection limit, precision and reagent consumption）, recoveries of standard compounds added to distilled water and analysis of 22 different natural samples. Recoveries of nitrogen compounds of the three simultaneous digestion procedures were quantitative limit from 97.2% to 101.3%. Recoveries of phosphorus from phosphorus compounds of the simultaneous digestion procedures were quantitative limit from 95. 8% to 100. 8%. In the analysis of 22 different natural water samples, total phosphorus and total nitrogen results obtained by three simultaneous digestion procedures were similar to that by the standard procedure （P 〉 0. 05）. Three simultaneous digestion reagents, specific to a single digestion for the continuous determination of total nitrogen and phosphorus, can be a substitute for national standard method for determination of TN and TP and economize the consumption of chemical reagents. However, the digestion reagent I and I1 had a potential of underestimate of TP and TP respectively for determining samples polluted seriously.