4-(4-氯苯重氮氨基)-4'-硝基偶氮苯的合成及其与镉(Ⅱ)的显色反应  

Synthesis of 4-(4-chlorophenyldiazoamino)-4'-nitroazobenzene and its color reaction with cadmium(Ⅱ)

作　　者：王贵芳[1] 邢云[1] 

机构地区：[1]安阳师范学院化学化工学院,河南安阳455002

出　　处：《冶金分析》2009年第5期20-23,共4页Metallurgical Analysis

基　　金：河南省科技攻关计划项目(082102270035);河南省教育厅科技攻关课题(2008B150001)

摘　　要：合成了一种新显色剂4-（4-氯苯重氮氨基）-4＇-硝基偶氮苯（简称CDANA），并研究了该试剂与Cd（Ⅱ）的高灵敏显色反应。在60～65℃温度下，亚硫酸氢钠与甲醛反应半小时之后滴入苯胺生成苯胺基甲基磺酸钠，另将硝基苯胺重氮化得到重氮盐溶液滴入苯胺基甲基磺酸钠中得到4＇-硝基-4-氨基偶氮苯，然后将其滴入氯苯胺重氮化后的重氮盐溶液中，得经红外光谱检验和元素分析证实的目标产物。分光光度的研究结果表明，在Triton X-100存在下，于pH10．5的Na2B4O7-NaOH缓冲介质中，镉（Ⅱ）与试剂形成1：2的橙红色络合物，其最大吸收波长位于558nm处，表观摩尔吸光系数为1．42×10^5L·mol^-1·cm^-1，镉（Ⅱ）的质量浓度在0～0．75μg／mL范围内服从比尔定律。所拟方法用于废水中微量镉的直接测定，结果与原子吸收光谱法一致。The synthesis of a new reagent 4-（4-chlorophenyldiazoamino）-4＇- nitroazobenzene （CDANA） and its colour reaction with cadmium（Ⅱ） was studied. After sodium bisulfite reacted with methanal at 60--65℃ for 0.5 h, aniline was dripped into the system to synthesize phenylaminomethyl-sodium sulfonate, subsequently, the diazol solution of p-nitroaniline was dripped into phenylaminomethyl-sodium sulfonate synthesized to form 4＇-nitro-4-aminoazobenzene. The compound was then added into diazol solution of p-chloroaniline to obtain the object product, which was identified by IR spectrum and element analysis. The spectrophotometric result showed Cd（Ⅱ） reacted with CDANA, forming an orange-red complex in borax-NaOH buffer solution at pH 10. 5 in the presence of Triton X-100. Its apparent molor absorptivity was 1.42 × 10^5 L · mol^-1 · cm^-1 at the maximium absorption at 558 nm. Beer＇s law was obeyed in the concentration range of 0--0.75 μg/mL for Cd（Ⅱ）. The method has been applied to the determination of cadmium directly in waste water and the results were in agreement with those obtained by atomic absorption spectrometry.

关 键 词：4-(4-氯苯重氮氨基)-4'-硝基偶氮苯 镉 分光光度法 合成 

分 类 号：O657.32[理学—分析化学]