The Gas Sample Collection And Testing Methods And Applications

The gas is characterized by its easy diffusion and amorphousness, and their volume varies according to pressure. So there are many difficulties on gassy qualitative and quantitative analysis, especially, for mixed gases which are hardly determined if they were not separated. Meanwhile, its easy diffusion and the increasing trend of entropy make the separating more difficult. So ti is very important to research the testing methods of gases and mixed.This research mainly focuses on the quantitative and qualitative analysis of gas and volatile organic compounds (VOCs). Basing on the low boiling point of permanent gas and VOCs, it is appropriate to be analyzed in the form of gas. Besides, the collected method, pretreatment, analytical methods and instruments of gas and VOCs are similar in general. The analytical methods of them were studied intensively and systematically in detail in this paper through five parts as follows:1. Review. After searching and analyzing the related literatures, the author reviewed the analytical methods and knowledge-related of gas and VOCs.2. Inventing a device using for trapping gas and VOCs which can be applied analytical research by examining its performances.3. Inventing the vacuum headspace gas chromatography and considering the advantages and disadvantages of heat headspace methods and vacuum headspace gas chromatography, it would be wonderful to combine these two methods together. In this study, the combination method was used in detecting remaining amount of methanol and No.6 solvent-extracted oil in edible oil.4. Studying on the quantitative and qualitative analysis of gas and organic matter in Hydrocarbon source rock by headspace gas chromatography. The VOCs collected by two pretreatment methods were analyzed quantitatively with gas chromatography.5. Studying on the gases which from the process of carborundum (SiC) productive by GC-MS and GC. The manufacturing technique of SiC in this article is Chemical Vapor Deposition (CVD) and the producing plant is methyltrichlorosilane and hydrogen(MTS/H2). During the process of SiC production, the complex gas components such as corrosive HCl, chlorosilane and a small amountof hydrocarbon gas were caused. The ingredients and contents of these gases effect on deposition and deposition rate of SiC material and reflect the deposition mechanism, So it is important to the measurement of the gases. However, it is very difficult for the mixed gas to be separated with the same column, and for which is not suitable to be analysised into equipment directly as their highly corrosive. By selecting the suitable separation method and reagent, the samples were preseparated successfully, at the same time HCl was measured by derivating it into butyric acid. Finally, HCl gas from mixed gas sample and chlorosilane hydrolyzate was determined respectively with isotope exchange reaction method.