利用紫外/可見光光譜法進行過醋酸之光譜分析及其定量

Abstract

本研究主要基於利用紫外-可見光光譜 (Ultraviolet–visible spectroscopy, UV-Vis) 對過醋酸 (peracetic acid, PAA) 進行光譜分析，而過醋酸標準品在紫外-可見光光譜中無法觀察到波峰，將其濃度稀釋60倍後，依然無法觀察到波峰，接續再對其處於平衡態時之各物質進行光譜測量，發現無法透過比爾定律 (Beer’s law) 進行其濃度分析，因此利用選定特定波長之吸收度、特定波長範圍面積積分以及特定吸收度之波長等三種方式，進行過醋酸與其關係之濃度分析，並比較其定量結果。搭配監測自行合成過醋酸過程，透過由傅立葉轉換紅外光譜儀 (Fourier-transform infrared spectroscopy, FTIR) 得到反應過程各時間中過醋酸之濃度後，使用解聯立方程式，找出紫外-可見光光譜所能夠準確分析過醋酸濃度且不被其他成分干擾的定量方式，透過實驗及數據分析可以得到，在特定的吸收度底下，波長能與濃度的對數呈線性關係，而進一步推論其成因，同時此方法可用於過醋酸之定量及反應過程的濃度測定，以及未來能夠用於儀器設計，使得過醋酸之應用更加有效率。

This study is based on using Ultraviolet–visible spectroscopy (UV-Vis) to analysis the spectrum of peracetic acid (PAA). UV/vis spectrum of PAA standard or diluted 60 times sample show no characteristic peaks. Next, detecting each component of PAA, we can find that it can't obey the Beer's law and hard to quantification via other component. We use absorbance at certain wavelength, area at certain wavelength range, wavelength at certain absorbance, and compare their result of PAA's quantification. Applying the [PAA] during the reaction process calculated from Fourier-transform infrared spectroscopy (FTIR) into the method used at UV-vis spectrum by solving the equation, we can find that there is a linearity between wavelength at certain absorbance and logarithm ofconcentration of peracetic acid, and estimate the reason of linearity, this method can fit the reaction and the standard dilution for quantification at the same time. This method also can apply to instrument design in the future, makes the application of PAA more efficient.