摘要
合成了新显色剂1 (6 羟基 2 嘌呤基) 3 [4 (苯基偶氮)苯基] 三氮烯(简称HPAPT),研究了它的性质及其与镉显色反应的条件。实验表明,试剂的分子式为C17H13N9,相对分子质量为359,熔点127～129℃,各级酸离解常数为pKa1=4.1,pKa2=7.2,pKa3=10 7。在pH9.0～11.0的Na2B4O7 NaOH缓冲介质中,试剂与镉形成2∶1的红色络合物,表观摩尔吸光系数为2 25×105L·mol-1·cm-1,镉质量浓度在0～0.6mg/L范围内符合比耳定律,在联合掩蔽剂的作用下,可不经分离直接测定环境水样和工业废水中微量镉。
The synthesis of reagent 1-(6-hydroxy-2-pynne)-3-(4-phenylazo-phenyl)-Triazene (HPAPT) and the condition of its reaction with Cadmium are reported. The composition and structure of the reagent are determined by elemental analysis and IR spectroscopy. Its dissociation constants are: pKa_1=4.1,pKa_2 =7.2,pKa_3=10.7, nm. In the presence of Triton X-100 the reagent reacts with cadmium (Ⅱ) to form a red complex with the molar ratio of 2∶1 in pH9.0～11.0 Na_2B_4O_7-NaOH buffer solution. The maximum absorption of the complex is at 530 nm and the apparent molar absorptivity is 2.25×10~5 L^(-1)·mol^(-1)·cm^(-1), Beer′s law is obeyed for Cadmium (Ⅱ) in the range of 0～0.6 mg/L. The method has been applied to the direct determination of Cadmium (Ⅱ) in practical samples with satisfactory results.
出处
《分析试验室》
CAS
CSCD
北大核心
2005年第1期11-13,共3页
Chinese Journal of Analysis Laboratory
基金
山西省教育厅高科技开发资助项目(9805023)
山西省自然科学基金资助项目(9905003)
关键词
HPAFF
镉
显色反应
Cadmium
1-(6-hydroxy-2-pyrine)-3-(4-phenylazo-phenyl)-Triazene
Spectrophotometry
