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Updated: Sep 8, 2025
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Quantitative Analysis by Thermogravimetry-Mass Spectrum Analysis for Reactions with Evolved Gases
Published on: October 29, 2018
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A qualitative analysis method for multi-component gas mixtures via terahertz rotational spectroscopy
Jia Li1, Xiaojiao Deng1, Xiaoping Zheng1
1Department of Automation, Beijing National Research Center for Information Science and Technology, Tsinghua University, Beijing 100084, China. asean@mail.tsinghua.edu.cn.
Analytical Methods : Advancing Methods and Applications
|June 14, 2022
Summary
This study introduces a new terahertz spectroscopy method using collision broadening to identify gases in mixtures. This technique enhances gas sensing accuracy for complex chemical analyses.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Physical Chemistry
Background:
- Terahertz rotational spectroscopy is a powerful gas sensing technique.
- Identifying components in multi-component gas mixtures is challenging due to dense spectral peaks.
- Existing methods struggle with complex spectral overlaps in the terahertz range.
Purpose of the Study:
- To develop a novel qualitative analysis method for multi-component gas mixtures.
- To utilize the collision broadening mechanism in conjunction with terahertz spectroscopy.
- To improve the accuracy and ease of gas identification in complex mixtures.
Main Methods:
- Established a database of collision broadening coefficients for acetonitrile, formic acid, and formaldehyde with nitrogen via experimental measurements and spectral peak fitting.
- Derived broadening coefficients for isolated peaks in binary and ternary gas mixtures perturbed by nitrogen.
- Identified gas components by matching derived broadening coefficients with the established database.
Main Results:
- Successfully created a broadening coefficients database for key chemical species.
- Demonstrated the derivation of broadening coefficients for mixed gas systems.
- Validated the identification of components in gas mixtures using the proposed method.
Conclusions:
- The collision broadening mechanism offers a new approach for qualitative analysis of multi-component gas mixtures.
- This method enhances the capabilities of terahertz spectroscopy for complex gas sensing applications.
- The technique provides a valuable tool for analytical chemistry, particularly in identifying unknown gas compositions.
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