Fabracation And Research Of Malodorous Gases Portable Fast Gas Chromatography Apparatus

Volatile Organic Compounds(VOC)is the major pollutants of the atmospheric environment, including benzene and its derivatives, ethers, organic amines, lipids, chlorinated hydrocarbons and chlorinated benzene, volatile phenol. It is known that VOC are toxic, pathogenic and carcinogenic. Moreover, the VOC can lead to the greenhouse effect and other environmental hazards. Some other volatiles such as methyl sulfide, methyl mercaptan, dimethyl disulfide, carbon disulfide, trimethylamine, styrene, and inorganic gases are malodorous gases, and most of the malodorous gases are chalcogenide material. In addition to these hazards, the material has a strong irritation that will damage the living environment. For the environmental monitor,it is essential to develop portable devices which perform both highly sensitivity and rapidly detection in the environment.In the dissertation, the gas chromatography apparatus have been investigated. It can rapidly separate the mixed sulfur gas which includes methyl sulfide, methyl mercaptan, dimethyl disulfide, carbon disulfide. In order to build the malodorous gases portable detection equipment, the gas chromatography apparatus have to be combined with preconcentrator and surface acoustic wave gas sensor. The main results were as follows.Firstly, the principle of the gas chromatography was analyzed. And then based on the principle of the conventional gas chromatograph, the optimal separation conditions for separation of the mixture of four gases have been investigated. Different experimental parameters including heating methods, pre-column pressure, inlet temperatures and detector temperature are considered in the designation.In order to miniaturize the gas chromatograph, a portable gas chromatograph device has been designed and assembled. The device can separate the sulfur mixture rapidly. The sulfur mixture includes dimethyl sulfide, methyl mercaptan, dimethyl disulfide, carbon disulfide.The apparatus consist of a temperature control device, a capillary column, heating devices, thermal devices, and a flame photometric detector in the back. Temperature control device can make the capillary column be heated rapidly; and the insulation devices can maintain the temperature of the capillary column. The flame photometric detector can effectively distinguish different gases, and achieve qualitative analysis of the sulfur-based gas mixture.