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The Use of Forensic Polycyclic Aromatic Hydrocarbon

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The Use of Forensic Polycyclic Aromatic Hydrocarbon The use of Forensic Polycyclic Aromatic Hydrocarbon Signatures and Compound Ratio Analysis Techniques (CORAT) for the Source Characterisation of Petrogenic / Pyrogenic Environmental Releases Mr Ken Scally Master of Science (Research) Galway Mayo Institute of Technology (GMIT) Dr Myles Keogh Dr Gay Keaveney Submitted to the Higher Education and Training Declaration The contents of this thesis have not been submitted as an exercise for a degree at this or any other College or University. The contents are entirely my own work. The sample location is anonymous to provide confidentiality in this study. Permission is required from die author before a library can lend this thesis. ^ II jf \,fo°\ | 4 (A A.C-S Cf 1 Signed: ^ L t y / u 6 ~ > d - Ken Scally BSc (Hons), MICI, ISEF Dedication To Pauline and my Parents Table of Contents Table of Contents Page N um ber Declaration.................................................................................................................................................................. iii Dedication........................................................................................................................ ........................................ iv Table of Contents....................................................................................................................................................... v List o f Figures............................................................................................................................................................ vii List o f Tables.............................................................................................................................................................. viii List of Equations........................................................................................................................................................ viii Acknowledgements................................................................................................................................................... ix Abbreviations.............................................................................................................................................................. x Abstract................................................................................................................................................................ xiv Chapter 1 Introduction and Literature Review............................................................................................. 2 1.0 Origins of Hydrocarbon Species in Soil........................................................................................... 2 1.1 Components of Hydrocarbons Found at Contaminated Sites.............................. ................... 2 1.2 Petroleum Chemistry........................................................................................................................... 3 1.3 Analytical Approach for Fingerprinting Petroleum...................................................................... 6 1.4 V P H - Gasoline.............................................................................. ...................................................... 9 1.5 E PH -K erosene and Jet A -1.............................................................................................................. 10 1.6 E P H -D iese l......................................................................................................................................... 11 1.7 Lubrication O il..................................................................................................................................... 13 1.8 Poly cyclic Aromatic Hydrocarbons (PAHs).................................................................................. 14 1.9 Coal Tar Chemistry.............................................................................................................................. 15 1.10 Behaviour of Oil in the Environment............................................................................................... 16 1.10.1 Spreading of Oil Following Release............................................................................... 17 1.10.2 Weathering Process - Evaporation................................................................................. 17 1.10.3 Dissolution............................................................................................................................ 18 1.10.4 Photo-oxidation a Weathering Process........................................................................... 18 1.10.5 Dispersion.............................................................................................................................. 18 1.10.6 Emulsification...................................................................................................................... 19 1.11 Environmental Factors Affecting Oil Biodégradation.................................................................. 19 1.11.1 Weathering Processes........................................................................................................ 19 1.11.2 Temperature......................................................................................................................... 20 1.11.3 Oxygen.................................................................................................................................. 20 1.11.4 Nutrients............................................................................................................................... 21 1.11.5 Other Factors........................................................................................................................ 21 1.12 Biodégradation o f Oil........................................................................................................................... 23 1.12.1 Mechanism of Oil Biodégradation, Hydrocarbon-Degrading Micro­ organisms............................................................................................................................. 23 1.12.2 Biodégradation of Aliphatics............................................................................................ 23 1.12.3 Biodégradation of Aromaiics............................................................................................ 24 1.12.4 Biodégradation o f Resin and Asphaltenes................................................................... 24 1.13 Weatlrering Check and Biodégradation Check........................ .................................................. 25 Chapter 2 Methodology......................................................................................................................................... 27 2.0 Instrumentation...................................................................................................................................... 27 2.1 Solvents and Reagents.......................................................................................................................... 28 2.2 Sample and Reference Material Extraction..................................................................................... 29 2.3 Manual Shake Extraction for Coal, Road Tar, South American Crude Bitumen and Sample S - l........................................................................................................................................... 29 2.4 Extraction Reference Material - Kerosene, Diesel, Jeyes Fluid and Lubrication Oil 30 2.5 Volatile Hydrocarbon Analysis (VH)............................................................................................... 30 2.6 Volatile Hydrocarbons (VH) Analytical Procedure....................................................................... 30 2.7 Polycyclic Aromatic Hydrocarbons (PAH) Analytical Procedure............................................. 31 v Table of Contents Page N um ber 2.7.1 Extractable Hydrocarbons (EH) Analytical Procedure................................................... 31 Chapter 3 Discussion of Results............................................................................................................................ 33 3.0 Introduction............................................................................................................................................... 33 3.1 Gas Chromatography Analysis of Petroleum Products.................................................................... 33 3.2 Level 1 Chemical Fingerprint by GC-FID......................................................................................... 35 3.3 Level 2 Detailed Analysis be GC-M S................................................................................................. 35 3.4 Level 3 Statistical Analysis of the Data.............................................................................................. 36 3.5 Compound Ratio Analysis Technique (CORAT)............................................................................. 36 3.6 Level I Investigation Chemical Fingerprinting by GC-FID Characterising the Sample by Obtaining the Overall Boiling (Carbon) Range of the Contaminants .............................. 40 3.6.1 Comparing Distribution Patterns/Profiles........................................................ 40 3.6.2 Analysis of Extractable Hydrocarbons (EH).............................................................. 42 3.6.2.1 Characterising Overall Boiling (Carbon) Range of the Contaminants...................................................................................................
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