TBP碳糊修饰电极三元络合物体系测定痕量铅(Ⅱ)

Determination of Lead by Chemically Modified Carbon Paste Electrode of TBP

研制了磷酸三丁酯（ＴＢＰ）碳糊修饰电极，在含１－苯基－３－甲基－４－苯甲酰基－５－吡唑酮（ＰＭＢＰ）的ＨＣｌ－ＫＣｌ底液中，通过电位富集，将三元络合物Ｐｂ（ＰＭＢＰ）２（ＴＢＰ）２中的铅富集在电极上，用２．５次微分阳极溶出伏安法测定铅．铅浓度在１．０×１０－９～２．５×１０－７ｍｏｌ·Ｌ－１范围内与峰高呈良好的线性关系．该电极用于铜合金和废水中铅的测定，获得满意结果．

A chemically modified carbon paste electrode was prepared by incorporating tributyl phosphate(TBP) directly into the paste mixture. In the presence of 1 phenyl 3 methyl 4 benzoyl 5 pyrazolone(PMBP), trace lead in HCl KCl supporting electrolyte can be preconcentrated on the electrode. The method showed good linearly for 1.0×10 -9 -2.5×10 -7 mol·L -1 lead(Ⅱ). Many common metal ions have no or little effect on the determination of lead(Ⅱ). The electrode was verified by the determination of trace lead(Ⅱ) in the waste water and alloy.