Application And Investigation Of Volatile Compound Analysis By Adsorption-thermal Desorption

Thermal Desorption is a novel sample preparation method for extracting and analyzing the volatile and semi-volatile compounds in complex sample, the method without using any of organic solvents is easy to operate, also it has high sensitivity, the detection limit achieves 10^-9level. Now it has been applied to analyze environmental samples, food and drink, drugs, plants, mineral and so on, almost any of the samples containing volatile organic compounds can be analyzed by this method, expands the scope of the analysis greatly by gas chromatography.In this paper, the application of thermal desorption was studied. A reasonable experimental program was established by optimizing adsorption and desorption conditions,.the volatile compounds especially the low boiling point compounds in tobacco, tobacco flavor sample and volatile organic air pollution in automobile were determined by thermal desorption/gas chromatography/mass spectrometry.In Chapter 1, the principle and application progress of thermal desorption, the research status of tobacco, tobacco flavor, and air pollution in automobile were Summarized. the law applying thermal desorption to tobacco and tobacco flavor aroma research was proposed, which could make up for the other sample treatment; Methods of thermal desorption will be used in car air pollution detection. Some preventive steps were pointed according to the determination. The relative sdandard of pollution compounds jn air was brought forward because of no national sdandard for the air quality in automobile.In Chapter 2, the application of Tenax TA adsorpt/thermal desorption/gas chromatography/mass spectrometry to determine the low boiling point volatile in tobacco was studied. A reasonable thermal desorption experiment program was established. The different tobacco samples were analyzed by this method. In addition the results of themal desorption method were compared with that of the Simultaneous distillation extraction (SDE) method. Experimental results show that this method especially suitable for the determination of low boiling point volatile compounds in tobacco, it can make up for the other sample treatment.In Chapter 3, The application of Tenax TA adsorpt/thermal desorption/gas chromatography/mass spectrometry to determine the low boiling volatile point in tobacco flavor was studied. A reasonable thermal desorption experiment program was established. Different samples of tobacco flavor were analyzed by this method. In addition the two results getted from new method and the ultrasonic (ultrasound-assisted solvent extraction, UASE) solvent extraction method(UASE) were compared. Experimental results also show that this method especially suitable for the determination of low boiling point volatile compounds in tobacco flavor, it can make up for the other sample treatment.In Chapter 4, the air pollution in automobile of formaldehyde, benzenes and volitiled organic compounds were determined by Tenax TA adsorpt/TD/GC/MS and spectrophotometry methods. Some preventive steps were pointed according to the determination. The relative sdandard indeies of pollution compounds have beed brought forward because of no national sdandard for the air quality in automobile.