离心法应用于高浊度地表水中氨氮测定预处理过程中的方法

比较多种预处理方法去除浊度对地表水氨氮测定的影响,结果表明在测定高浊度地表水氨氮的过程中,采用离心法可较好地去除悬浮物对水样测定的干扰。较清水样用比色前离心方法,对于较浑浊的水样用絮凝沉淀结合比色前离心方法,可明显去除浊度的干扰,得到稳定的氨氮数值。2种方法的准确度和精密度均满足质控要求。

Methodological Investigation on the Application of Centrifugation during the Pretreatment Step of Ammonia Nitrogen Determination in High Turbidity Surface Water

By comparing the efficiencies of various pretreatment methods in removing the turbidity effect on the determination of ammonia nitrogen in high turbidity surface water,it was found that centrifugation could fairly reduce interferences of the suspended substance.For clear water samples,centrifugation before colorimetric measurement can effectively remove the turbidity interference,and for water samples with high turbidity,it is more effective to combine flocculation precipitation with centrifugation before colorimetric measurements.These two pretreatment methods show high accuracy and precision that comply with quality control.