【作者】 李岩；

【导师】 姚俊学；

【作者基本信息】 内蒙古大学 ， 环境科学， 2009， 硕士

【摘要】 本论文对Mn²⁺-phen-SCN^-、Mn²⁺-Dipy-SCN^-两个三元络合体系共沉淀水中的铜、锌、镉、铅进行了研究。重点探讨了载体离子的选择、共沉淀剂加入顺序、共沉淀剂加入量、pH值、共存离子的干扰等因素对共沉淀作用的影响,确定了最佳的共沉淀条件。实验结果表明,Mn²⁺-phen-SCN^-三元络合体系对Cuz²⁺、Zn²⁺、Cd²⁺、pb²⁺均有很好的共沉淀效果。Cu²⁺离子浓度为0.01mg/L时,测定精密度为1.41%（n=11）,检出限为5.08μg/L（3σ）。标准加入法测得桃李湖水中Cu²⁺的含量为4.93μg/L,回收率在97%-105%之间。Zn²⁺离子浓度为0.01mg/L时,测定精密度为2.93%（n=11）,检出限为3.73μg/L（3σ）。标准加入法测得桃李湖水中Zn²⁺的含量为0.576μg/L,回收率在99%-103%之间。Cd²⁺离子浓度为0.01mg/L时,测定精密度为3.18%（n=11）,检出限为1.64μg/L（3σ）。标准加入法测得桃李湖水中Cd²⁺的含量为0.618μg/L,回收率在97%-101%之间。pb²⁺离子浓度为0.1mg/L时,测定精密度为2.27%（n=11）,检出限为24.2μg/L（3σ）。标准加入法未检出兴安盟长寿水中的pb²⁺,加标回收率在98%-101%之间。Mn²⁺-Dipy-SCN^-三元络合体系则对Cd²⁺有较好的选择性。Cd²⁺离子浓度为0.01mg/L时,测定精密度为2.83%（n=11）,检出限为1.91μg/L（3σ）。标准加入法测得桃李湖水中Cd²⁺的含量为0.630μg/L,回收率在98%-101%之间。Mn²⁺-phen-SCN^-、Mn²⁺-Dipy-SCN^-两个三元络合物共沉淀体系对重金属离子Cu²⁺、Cd²⁺、Zn²⁺、Pb²⁺有很好的分离富集效果,富集因子达50倍以上,消除了基体干扰。整个实验方法具有灵敏度高,检出限低,精密度高,回收率满足痕量元素分析准确度的要求等优点,为火焰原子吸收分光光度法测定水体中痕量Cu²⁺、Cd²⁺、Zn²⁺、Pb²⁺等环境危害性显著的重金属离子提供了新的分析方法。更多还原

【Abstract】 In this paper, the co-precipitation of Mn²⁺-phen-SCN^-, Mn²⁺-Dipy-SCN^- two ternary complex systems for copper, zinc, cadmium and lead in the water were studied. Focus on the choice of the carrier ion, co-precipitation agent to join the order, a total amount of precipitant, pH, ions and other factors on the interference effects of co-precipitation to determine the best conditions for co-precipitation. The results show that the Mn²⁺-phen-SCN^- ternary complex system shows a better concentration effect for Cu²⁺, Cd²⁺, Zn²⁺. When the concentration of Cu²⁺ is 0.01mg/L, the measured precision is 1.41% （n=11）, the detection limit is 5.08μg/L （3s）. The concentration of Cu²⁺ in the Taoli Lake is 4.93μg/L measured by standard addition method and the recoveries are 98%-105%. When the concentration of Zn²⁺ is 0.01mg/L, the measured precision is 2.93% （n=11）, the detection limit is 3.73μg/L （3s）. The concentration of Zn²⁺ in the Taoli Lake is 0.576μg/L measured by standard addition method and the recoveries are 99%-103%. When the concentration of Cd²⁺ is 0.01mg/L, the measured precision is 3.18% （n=11）, the detection limit is 1.64μg/L （3s）. The concentration of Cd²⁺ in the Taoli Lake is 0.618μg/L measured by standard addition method and the recoveries are 98%-101%. When the concentration of Pb²⁺ is 0.01mg/L, the measured precision is 2.27% （n=11）, the detection limit is 24.2μg/L （3s）. Standard addition method doesn’t detect Pb²⁺ in the Xing’an League water, and the recoveries of standard addition are 98%-101%. The Mn²⁺-Dipy-SCN^- ternary complex system has a good selectivity to Cd²⁺. When the concentration of Cd²⁺ is 0.01mg/L, the measured precision is 2.83% （n=11）, the detection limit is 1.91μg/L （3s ）. The concentration of Zn²⁺ in the Taoli Lake is 0.630μg/L and the recoveries are 98%-101% measured by standard addition method.The Mn²⁺-phen-SCN^-, Mn²⁺-Dipy-SCN^- two ternary complex co-precipitation systems have good concentration effects for Cu²⁺, Cd²⁺, Zn²⁺ and Pb²⁺, whose enrichment factors get to 50 times, basically eliminate the matrix interference. The experimental method has high sensitivity, low detection limits, precision, recovery of trace element analysis to meet the requirements of accuracy, etc. The method provides a new way for the flame atomic absorption spectrophotometry to determinate the trace Cu²⁺, Cd²⁺, Zn²⁺, Pb²⁺and the other environment significant danger of heavy metal ions in the water, which has a certain value.更多还原