三重四极杆电感耦合等离子体质谱法测定水中痕量磷的方法建立及在新安江水库的应用

Establishment of a Method for the Determination of Trace Phosphorus in Water by ICP-MS/MS and Its Application in Xin\anjiang Reservoir

建立了三重四极杆电感耦合等离子体质谱法(ICP-MS/MS)测定地表水中痕量总磷、溶解态磷、颗粒态磷的方法,确定了ICP-MS/MS测定水中磷的仪器参数及氧气流量。研究了该方法检测水中磷元素的检出限、精密度、正确度,探索了浊度、色度及砷、铬、硫的存在对ICP-MS/MS测磷的影响。结果表明,采用高纯氧气反应ICP-MS/MS法可对地表水中的各形态痕量磷进行质量浓度检测,该方法的检出限可达0.24μg/L,磷元素在1.00~1000μg/L质量浓度范围内具有良好的线性,相关系数为0.9995,加标回收率为92%~103%。该方法检测速度快,抗浊度、色度及共存元素(砷、铬、硫)干扰的能力强。对新安江水库4个季度的总磷、溶解态磷、颗粒态磷进行测定,结果表明,水库总磷平均质量浓度为10~20μg/L,ρ(溶解态磷)/ρ(总磷)为42.4%~50.9%。该方法可以满足地表水中痕量磷的快速测定及形态分析。

An inductively coupled plasma coupled with triple quadrupole mass spectrometric(ICP-MS/MS)method was established for the determination of trace total phosphorus(TP),dissolved phosphorus(DP)and particulate phosphorus(PP)in surface water samples.The instrument parameters and oxygen flow rate for the determination of phosphorus in water by ICP-MS/MS were determined.The detection limit,precision and accuracy of the method for the determination of phosphorus in surface water were studied.The effects of turbidity,chromaticity and the presence of arsenic,chromium and sulfur on the determination of phosphorus by ICP-MS/MS were explored.The results show that trace phosphorus in surface water can be detected by ICP-MS/MS with high purity oxygen,and the detection limit of this method is 0.24μg/L,the method has good linearity in the range of 1.00~1000μg/L,the correlation coefficient is 0.9995,and the recoveries are between 92%to 103%.This method has fast detection speed and strong resistance to the interference of turbidity,chromaticity,arsenic,chromium and sulfur.The monitoring data of Xin\anjiang Reservoir in four quarters shows that the average concentration of TP in the whole lake of Xin'anjiang Reservoir is 10~20μg/L,the ratio of DP to TP is 42.4%~50.9%.ICP MS/MS method therefore can satisfy the determination and speciation analysis of trace phosphorus in surface water.