微波消解-离子色谱法测定地表水中痕量总磷

Determination of Trace Total Phosphorus in Surface Water by Microwave Digestion-Ion Chromatography

总磷是评价河湖地表水富营养程度的重要指标,但现阶段测定总磷常用的钼酸铵分光光度法、流动注射法、电感耦合等离子体发射光谱法等灵敏度较低,不能满足地表水I类质量标准中对总磷的测定需要。为降低总磷测定方法的检出限,将环境监测实验室常用的微波消解前处理技术和离子色谱的测定方法相结合,优化微波消解和离子色谱条件,方法检出限可达0.002 mg/L,能够满足总磷质量浓度低于0.01 mg/L地表水的测定需求,同时具有较强的抗浊度和色度干扰能力,准确度和精密度较好,自动化程度高,便于推广普及。

Total phosphorus is an important index to evaluate the eutrophication degree of rivers and lakes.However,at present,ammonium molybdate spectrophotometry,flow injection method,inductively coupled plasma emission spectrometry,et al.have low sensitivity for the determination of total phosphorus,which cannot meet the requirements of total phosphorus determination in grade I surface water.In order to reduce the detection limit of total phosphorus,the pretreatment technology of microwave digestion commonly used in environmental monitoring laboratory was combined with the determination method of ion chromatography.The conditions of microwave digestion and ion chromatography were optimized.The detection limit could reach 0.002 mg/L,and it is fit for the determination of total phosphorus in surface water with the concentration of less than 0.01 mg/L.And it has a strong ability to resist interference of turbidity and chroma,good accuracy and precision,high degree of automation,easy to popularize.