以微型空氣電弧放射光譜研製氣相層析儀偵測器
Abstract
本研究製作一空氣電弧氣體偵測器並實際應用於氣相層析儀進行揮發性有機氣體偵測。利用石英管與市售不銹鋼針頭製作簡易電弧裝置，將電極連接高壓產生器，施加正弦波形高壓交流電激發空氣產生電弧。以空氣作為氣相層析儀載流氣體，當待測物通過電弧時，有機物會減弱電弧放光強度，並利用光譜儀分析空氣電弧放射光譜。進一步進行光譜儀參數、載流氣體流速、電場梯度等條件最佳化。於最佳化條件下此空氣電弧氣體偵測器有良好之再現性，對12種有機氣體進行量測均有良好的線性關係（R2＞0.997）。透過不同官能基反應性比較，推測本研究製作之偵測器對於含氧類及芳香族化合物反應性較高。除有機樣品偵測外也將此偵測器應用於無機氣體量測。另與可攜式微型氣相層析儀之光游離偵測器進行比較，相較光游離偵測器本研究製作之空氣電弧氣體偵測器可偵測較高游離能之化合物。本研究製作之空氣電弧氣體偵測器具有裝置微小、成本低廉、再現性高及高靈敏度之優點，偵測下限可達到210 pg，並使用價格低廉之空氣作為載流氣體，期許未來能應用於微型氣相層析儀。
In this study, we developed an air arc gas detector, which can be used as a gas chromatography detector. A simple arc device was made using quartz tube and commercially stainless steel syringe needle. The electrodes were connected to a high-voltage generator. A sinusoidal wave high voltage alternating current(AC) was applied to the electrodes excited air to generate an arc. Air is used as carrier gas applied in gas chromatography. When organic compounds pass through the arc, the organic compound will weaken the emission intensity of the air arc, and the air arc emission spectrum is analyzed by a spectrometer. This study further optimized the parameters of the spectrometer, flow rate of carrier gas and electric field gradient. Under these optimal condition, the air arc gas detector has good reproducibility, and the measurement of 12 kinds of organic gases has a good linear relationship (R2>0.997). After comparing the reactions of different functional groups, it is concluded that the air arc detector developed in this study has higher reactivity towards oxygen-containing and aromatic compounds. In addition to the detection of organic samples, this detector is also used for the measurement of inorganic gases. Compared with the photoionization detector of a portable gas chromatography, the air arc gas detector in this study can detect compounds with higher ionization energy. This study successfully developed a new type of air arc gas detector with the advantages of device miniaturization, low cost, high reproducibility, and high sensitivity. The detection of limit can reach 210 pg, and low-cost air is used as the carrier gas. It is hoped that it can be applied to micro gas chromatography in the future.
In this study, we developed an air arc gas detector, which can be used as a gas chromatography detector. A simple arc device was made using quartz tube and commercially stainless steel syringe needle. The electrodes were connected to a high-voltage generator. A sinusoidal wave high voltage alternating current(AC) was applied to the electrodes excited air to generate an arc. Air is used as carrier gas applied in gas chromatography. When organic compounds pass through the arc, the organic compound will weaken the emission intensity of the air arc, and the air arc emission spectrum is analyzed by a spectrometer. This study further optimized the parameters of the spectrometer, flow rate of carrier gas and electric field gradient. Under these optimal condition, the air arc gas detector has good reproducibility, and the measurement of 12 kinds of organic gases has a good linear relationship (R2>0.997). After comparing the reactions of different functional groups, it is concluded that the air arc detector developed in this study has higher reactivity towards oxygen-containing and aromatic compounds. In addition to the detection of organic samples, this detector is also used for the measurement of inorganic gases. Compared with the photoionization detector of a portable gas chromatography, the air arc gas detector in this study can detect compounds with higher ionization energy. This study successfully developed a new type of air arc gas detector with the advantages of device miniaturization, low cost, high reproducibility, and high sensitivity. The detection of limit can reach 210 pg, and low-cost air is used as the carrier gas. It is hoped that it can be applied to micro gas chromatography in the future.
Description
Keywords
空氣電漿, 常壓電漿, 電弧, 氣相層析, 放射光譜, air plasma, atmospheric plasma, arc, gas chromatography, emission spectrometry