摘要
研究了显色剂2-（1，3，4-三氮唑偶氮）-5-二乙氨基苯甲酸（TZDBA）与镍的显色反应，试剂与镍在pH5．0的HAc—NaAc缓冲溶液中形成紫红色配合物，组成比为n（Ni^2＋）：n（TZDBA）=1：2，配合物表观摩尔吸光系数ε=3．82×10^4L·mol^-1·cm^-1。镍质量浓度在0～0．8mg／L范围内符合比尔定律。配合物形成后在强酸溶液中能稳定存在，有良好的选择性。方法不经分离直接测定铝合金和纯镁中的微量镍，测定结果与认定值相符。
In this paper, the conditions of color reaction of a reagent 2-（ 1,3,4-triazolylazo）-5-diethylamino-benzoic acid （TZDBA） with Ni2＋ are reported. It is found that this new color reagent reacts with Ni2＋ to form a stable purple red complex in the medium of HAe-NaAc at pH 5.0. The maximum absorption wavelength and apparent molar absorptivity are 560 nm and e = 3.82 ×10^4 L·moL^-1·cm^-1 respectively. Beer＇s law is obeyed in the range of 0 - 0.8 mg/L for nickel. The complex will not be decomposed by adding some mineral acids, while complexes formed by other coexisting ions will be decomposed with TZDBA, thus the selectivity is improved. The method has been applied to the direct determination of trace nickel in pure magnesium and alumunium alloy with satisfactory results.
出处
《分析试验室》
CAS
CSCD
北大核心
2007年第9期63-65,共3页
Chinese Journal of Analysis Laboratory
基金
浙江省教育厅计划课题(20050051)项目资助
