摘要：合成了2-(4-醛基苯基)咪唑[4，5-f]1,10-邻菲罗啉配体，并研究了该配体与锌(Ⅱ)作用的分子光谱性质。实验表明，在 pH 为6.86 的 KH2PO4-Na2HPO4 的缓冲体系中，该配体能与锌发生显色反应，锌与显色剂形成摩尔比为 1:2 的红色配合物，在波长 460 nm 处有最大吸收峰，摩尔吸收系数  = 1.42 × 104 L·mol – 1 cm– 1，锌浓度在 1.53 ×10-6～1.22 ×10-5 mol/L范围内与吸光度呈良好的线性关系，线性回归方程为：A = 5.3036×10-6 c（mol/L）+0.05267，线性相关系数 r = 1.0351，桑德尔灵敏度 S = 2.28× 10-3 μg/cm2。用该方法测定茶叶和鸡蛋黄中的微量锌，分析结果的相对标准偏差均小于 2.5 %，加标回收率为 99.2% 和 100.0%。53384

毕业论文关键词：2-(4-醛基苯基)咪唑[4，5-f]1,10-邻菲罗啉配体，可见分光光度法，显色反应，锌

Abstract: 2 - (4 - aldehyde group phenyl) imidazole (4, 5 - f] 1, 10 phenanthroline ligands was synthesized and used as analytical reagent for the determination of zinc(Ⅱ). The optimal conditions for complex formation of this Schiff Base with zinc(Ⅱ) were established. In the pH of 6.86 , a red colored coordination complex was formed between the new color reagent and zinc(Ⅱ) with a mole ratio (R: zinc) of  2:1 , and its positive absorption maxima was found at the wavelength 460 nm. A = 5.3036×10-6c（mol/L）+0.05267, the calibration curve of zinc(Ⅱ) with good linearity (r = 0.98942) was obtained over the range of 1.53 ×10-6～1.22 ×10-5mol/L. The apparent molar absorptivity was 3.0866 × 104 L·mol -1·cm-1, and its Sandell sensitivities was found to be 2.28 × 10-3 μg/cm2. The method was applied to determine zinc(Ⅱ) in tea and eggs with satisfactory results.The values of RSD′s obtained were less than 2.5% , and results of recovery test were 99.2% and 100.0%.

Keywords: 2 - (4 - aldehyde group phenyl) imidazole (4, 5 - f] 1, 10 phenanthroline ligands， spectrophotometry，color  reaction， zinc(Ⅱ)

目   录

1  前言 4

2  实验部分 4

2.1  仪器、试剂、材料 4

2.1.1  试剂配制 5

2.1.2  样品的处理 5

2.2  实验方法 5

2.2.1 配体L的合成 5

2.2.2  配体L的结构表征 6

2.2.3  测定方法 7

3  结果与讨论 7

3.1  吸收光谱 7

3.2  实验条件的选择 7

3.2.1  酸度对体系吸光度的影响 8

3.2.2  缓冲溶液的用量对体系吸光度的影响 9

3.2.3  显色剂用量对体系吸光度的影响 9

3.2.4  显色温度对体系吸光度的影响 10

3.2.5  显色时间对体系吸光度的影响 10

3.3  配合物的组成 11

3.4  共存离子的影响 11

3.5  工作曲线及灵敏度 12

4  样品分析 14

4.1  样品及精密度的测定 14

4.2  加标回收试验