论文部分内容阅读
用多种电化学方法研究了Pb(Ⅱ)与1-苯基-3-甲基-4-(α-噻吩甲酰基)-5-吡唑啉酮(HPM?TP)配位吸附波的性质及反应机理。考察了支持电解质、体系pH值、配体用量、扫描的起始电位、扫描速度等对电极反应的影响。实验结果表明,在HAc-NaAc(pH=3.1)介质中,于-0.51V(vs.SCE)处出现一尖锐、灵敏的极谱峰,此极谱波被证明为配合物的吸附波。Pb(Ⅱ)含量在0.002～8μg·mL-1与峰电流呈线性关系,峰电流由中心离子Pb(Ⅱ)还原产生。配合物的组成为Pb2+:HPMαTP=1:2。并将其用于粗盐、麦片、化妆品样品中铅的测定,结果令人满意。
The adsorption properties of Pb (Ⅱ) and 1-phenyl-3-methyl-4- (α-thiopoyl) -5-pyrazolone (HPM? TP) And reaction mechanism. The effect of supporting electrolyte, system pH value, ligand dosage, scanning initiation potential and scanning speed on the electrode reaction was investigated. The experimental results show that there is a sharp and sensitive polarographic peak at -0.51V (vs.SCE) in HAc-NaAc (pH = 3.1) medium, which is proved to be the adsorptive wave of the complex. The linear relationship between Pb (Ⅱ) concentration and peak current was found at 0.002-8μg · mL-1. The peak current was reduced by the central ion Pb (Ⅱ). The composition of the complex is Pb2 +: HPMαTP = 1: 2. And it is used for the determination of lead in coarse salt, cereal and cosmetic samples with satisfactory results.