光谱法锌离子检测系统的研究

采取标准锌显色剂与锌发生显色反应，生成不溶于水的絮状络合物。用光谱仪测它的吸光度，研究其特征谱与吸光度的特点，建立其浓度与特征波长吸光度间的数学模型。本文所采用的显色剂主要与锌、铜、镉、镍四种离子发生络合反应。因此分别探索了四种离子高浓度以及低浓度时显色反应的吸光度，最终通过得到锌离子浓度与吸光度的关系式以及锌离子浓度与四波长下四种离子混合溶液显色后的吸光度的关系式，给出了锌离子的吸光度与总吸光度的关系式。显色反应能否满足分光光度法的要求，主要与显色剂的性质有关，同时显色反应的条件也至关重要。因为在显色反应过程中，主要是锌离子与锌显色剂发生络合反应形成络离子，进而形成絮状络合物。络离子一般比较稳定，但在水溶液中也存在着电离平衡，也就是说当显色条件发生变化时，既有可能形成络离子，也有可能发生络离子的分解，从而影响络合反应的程度。显色条件包括显色剂用量、pH值、反应温度、显色时间、待测溶液的盐度以及浊度等。重点研究待测溶液的盐度对锌离子浓度测量值的影响，并通过实验给出影响规律以及校正模型。

Study on Spectrophotometric Determination of Zinc Ion

In this paper, the standard zinc coloring reagent and zinc color reaction result in water-insoluble flocculent complex. In addition, the absorbance was measured by spectrophotometer, the characteristic spectrum and the absorbance were studied, and the mathematical model was established between the concentration and the absorbance of characteristic wavelength. In this paper, color reagent mainly makes complexing reaction with zinc, copper, cadmium, nickel ion, so this study mainly explores the absorbance of four kinds of ions, such as high concentration and low concentration. Finally, through capturing the relationship between the concentration of zinc ions and the absorbance of the zinc ion, and getting the relationship between the concentration of zinc ions and the absorbance of the zinc ion as well as the absorbance of the four kinds of ions with four wavelengths, the relationship between the absorbance and the total absorbance of the zinc ion is given. During the experiment, the color reaction can meet the requirements of spectrophotometry, which is mainly because of the nature of the reagent, while the color reaction conditions are also essential. In the color reaction process, it is mainly zinc ions and zinc coloring agent complexation react to form complex ions, and flocculent complex. The ion is generally stable, but there is also ionization balance in the aqueous solution, that is when the color conditions change, the formation of complex ions may also occur in the decomposition of complex ions, thus affecting the degree of complex reaction . Color conditions include the amount of reagent, PH value, reaction temperature, color time, the salinity of the solution and turbidity. In conclusion, this paper focuses on the salinity of the solution to be measured on the measurement of zinc ion concentration, and gives the influence rule and calibration model through experiments.