摘要
A novel Ce(Ⅳ) ion-selective polyvinyl chloride(PVC) membrane electrode based on HDEHP and HEH/EHP as ionophore was successfully prepared. The factors affecting the response of Ce(Ⅳ) ion were investigated, such as membrane composition, internal solution, concentration of SO_4^(2–), and acidity in test solution. The best performance was obtained using the membrane with PVC:DBP:HDEHP:HEH/EHP:OA mass ratio of 75:175:5:5:5. The proposed electrode exhibited a Nernstian slope of 30.44 mV/decade for Ce(Ⅳ) ion over a linear concentration range of 1×10^(–5)–1×10^(–1) mol/L with the detection limit of 9.0×10^(-6) mol/L. The electrode showed stable response within the SO_4^(2–) concentration range of 0.1–1 mol/L and the acidity range of 0.25–1.2 mol/L H+. The proposed electrode showed high selectivity for Ce(Ⅳ) over a wide variety of interfering ions and a fast response time. It was used as an indicator in the potentiometric titration of Ce(Ⅳ) solution with H_2O_2 solution, and could also be used for the determination of Ce(Ⅳ) in real Ce(Ⅳ)-containing aqueous samples.
A novel Ce(Ⅳ) ion-selective polyvinyl chloride(PVC) membrane electrode based on HDEHP and HEH/EHP as ionophore was successfully prepared. The factors affecting the response of Ce(Ⅳ) ion were investigated, such as membrane composition, internal solution, concentration of SO_4^(2–), and acidity in test solution. The best performance was obtained using the membrane with PVC:DBP:HDEHP:HEH/EHP:OA mass ratio of 75:175:5:5:5. The proposed electrode exhibited a Nernstian slope of 30.44 mV/decade for Ce(Ⅳ) ion over a linear concentration range of 1×10^(–5)–1×10^(–1) mol/L with the detection limit of 9.0×10^(-6) mol/L. The electrode showed stable response within the SO_4^(2–) concentration range of 0.1–1 mol/L and the acidity range of 0.25–1.2 mol/L H+. The proposed electrode showed high selectivity for Ce(Ⅳ) over a wide variety of interfering ions and a fast response time. It was used as an indicator in the potentiometric titration of Ce(Ⅳ) solution with H_2O_2 solution, and could also be used for the determination of Ce(Ⅳ) in real Ce(Ⅳ)-containing aqueous samples.
基金
supported by the Key Program of National Natural Science Foundation of China(50934004)
National Natural Science Foundation of China(51274061)
Major State Basic Research Development Program of China(2012CBA01205)
Fundamental Research Supporting Project of Northeastern University(N110602006)