| 摘要 |
The invention is a process of selective and quantitatively removing and concentrating at least one selected ion present in low concentration with other ions in higher concentration in a multiple ion solution. The method comprises bringing a complexing agent for the selected ion(s) into contact with a sufficient determined quantity of said multiple ion solution to remove and concentrate the selected ion(s) from the multiple ion solution; removing the multiple ion solution, from which the complexing agent has removed the selected ions, from the complexing agent having the selected ion(s) complexed therewith, bringing the complexing agent complexed with selected ion(s) into contact with a determined quantity of receiving liquid to break the complex and remove the selected and concentrated ion(s) from the complexing agent and determining the concentration of selected ion(s) in the said receiving liquid from which the concentration of selected ion(s) in the multiple ion solution can be calculated. The metal ions in low concentration are often heavy metal ions, such as lead ions, and the process finds particularly advantageous utility in the determination of lead content in ppb in drinking water. The preferred apparatus for carrying out the process is a column packed with silica gel or silica-bonded macrocycle as the complexing agent. |
