Development of comprehensive two-dimensional gas chromatography for the analysis of volatile organic compounds in the atmosphere

The use of comprehensive two-dimensional gas chromatography (GC x GC) for the analysis of volatile organic compounds in the atmosphere will be presented. Three different systems have been used and developed each suited to a particular aspect of atmospheric VOC analysis. A method for the offline analysis of whole air samples using a commercial GC x GC system coupled to a time-of-flight mass spectrometer (TOFMS) has been developed and has been used during an aircraft campaign. Calibration and precision data for 60 hydrocarbon species are presented, with %RSD ranging from 0.56 to 14.78 % and LOD ranging from 0.01 - 0.61 pptv for a l L sample. The developed method was used during the RONOCO campaign and data for 39 hydrocarbon species re- ported. The system allowed for an investigation into the aromatic complexity of the samples and the effect of these aromatic species on atmospheric reactivity was also investigated. Further investigation into the VOC complexity in the atmosphere was also performed. The development of a portable valve based GC x GC system is also presented. The system uses total transfer methodology to allow for sensitive cryogen free modula- tion. Analysis of gasoline and tea tree was performed and the performance of the system was assessed using gasoline. The instrument was coupled to a thermal des- orption unit for the analysis of atmospheric VOCs and gave LODs of between 2-4 pptv for selected hydrocarbons in a l L sample. Further development of the system making it suitable for fieldwork is also presented. A third miniaturised GC x GC system has been developed, particularly suited for the analysis of biogenic VOCs. The system is compact, low power and cryogen free, with the large GC oven replaced with a novel direct column heating method. The small footprint, power and consumable requirement make this system suitable for deployment for analysis in remote locations.EThOS - Electronic Theses Online ServiceGBUnited Kingdo