The Analysis of Unfired Propellant Particles by Gas Chromatography – Mass Spectrometry: a Forensic Approach
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THE ANALYSIS OF UNFIRED PROPELLANT PARTICLES BY GAS CHROMATOGRAPHY – MASS SPECTROMETRY: A FORENSIC APPROACH A thesis presented to the Queensland University of Technology in fulfilment of the requirements for the degree of Masters of Applied Science (Research) by Shiona Croft Bachelor of Applied Science Under the Supervision of: Dr John Bartley School of Physical and Chemical Sciences Queensland University of Technology April 2008 $%675$&7 In Australia, the 0.22 calibre ammunition is the most encountered ammunition type found at a crime scene [1]. Previous analysis of gun shot residue (GSR) and unfired propellant has involved studying the inorganic constituents by Scanning Electron Microscopy or similar technique. However, due to the heavy metal build up that comes with some ammunition types, manufacturing companies are now making propellant that is safer to use. Therefore, it has become appropriate to study and analyse unfired propellant by other means. One such technique is unfired propellant analysis by gas chromatography – mass spectrometry (GC-MS). This technique focuses on the organic constituent make up of the propellant paying particular attention to diphenylamine, ethyl centralite and dibutyl phthalate. It was proposed that different batches of ammunition could be discriminated or matched to each other by using this technique. However, since the main constituents of unfired propellant are highly reactive, it was not possible to accomplish batch determination of ammunition. However, by improving extraction techniques and by removing oxygen (a catalyst for the degradation of diphenylamine) a superior method was established to help in the analysis of unfired propellant. Furthermore, it was shown that whilst differentiating batches of the same ammunition was not possible, the improved methods have helped identify different types of the same brand of ammunition. With the aid of future studies to fully explore this avenue, the analysis of unfired propellant could one day become an integral part of forensic science. The Analysis of Unfired Propellant Particles by Gas Chromatography-Mass Spectrometry: A Forensic Approach Shiona Croft ii 67$7(0(172)25,*,1$/$87+256+,3 The work contained in this thesis has not been previously submitted to meet requirements for an award at this or any other higher education institution. To the best of my knowledge and belief, the thesis contains no material previously published or written by another person except where due reference is made. Shiona Croft Date The Analysis of Unfired Propellant Particles by Gas Chromatography-Mass Spectrometry: A Forensic Approach Shiona Croft iii $&.12:/('*(0(176 I wish to thank all those people who over the past years have seen me through my best and my worst…. Firstly, to my supervisor Dr John Bartley (QUT) for your advise, patience and support throughout my research. Your expert knowledge and direction was greatly appreciated. In particular, your considerable experience with mass spectrometry and research methodologies. Also, for your endless endurance, patience and guidance with regards to the thesis write up. For all your help, I thank you. To the Queensland Police Service (Mr Gary Asmussen and the members of the Analytical Services Unit) for allowing me to take up this research but for also giving me the freedom to explore this project in the direction I thought most appropriate. Thank you. To my colleague and friend Dr Helen Panayiotou, thank you for your words of wisdom. Your encouragement and valuable direction when I felt lost was appreciated greatly. To my mum and dad who has been supportive from day one. Your support, enthusiasm and confidence in my abilities allowed me to have courage in my work. Thank you for never allowing me to give up – although I am too stubborn to do so! To my dear Chris, who everyday told me how proud of me he was. Thank you for putting up with the late nights and the stress. For your love, friendship and strength – I honestly could not have done this without you. You mean everything to me. To my brother Kevin, who I know is very proud of me. Thanks for your support Kev! The Analysis of Unfired Propellant Particles by Gas Chromatography-Mass Spectrometry: A Forensic Approach Shiona Croft iv To my Ouma and Grandad, Connie and Gerald Campbell, I wish you could be here but you are always in my thoughts. Thank you for your support and interest in my thesis. It means so much to me that even though you are far away your love and encouragement is not forgotten. I miss you. To my very much loved group of friends; Scott, Niki, Amy, Mick, Nikki and everyone else who has been there for me. Some of you have been around for more than a decade and your love, encouragement and support is never forgotten. You all mean the world to me and thank you for giving me the strength to go on. Finally, to all the post graduate students whom I may not have seen as much as I would have liked (since being off campus) but to my friend Dr Sarah Ede in particular, who constantly inspired me and who I always knew would do great things. Thank you. The Analysis of Unfired Propellant Particles by Gas Chromatography-Mass Spectrometry: A Forensic Approach Shiona Croft v 7$%/(2)&217(176 $%675$&7 ................................................................................................ II 67$7(0(172)25,*,1$/$87+256+,3 ................................III $&.12:/('*(0(176 ....................................................................IV 7$%/(2)&217(176.........................................................................VI /,672)),*85(67$%/(6 ............................................................VIII $%%5(9,$7,216..................................................................................XI ,1752'8&7,21............................................................................ 1 1.1 BACKGROUND .......................................................................................... 1 1.2 THE 0.22 CALIBRE AMMUNITION.............................................................. 1 1.2.1 The Cartridge ................................................................................... 2 1.2.2 The Projectile.................................................................................... 2 1.2.3 The Propellant .................................................................................. 3 1.2.4 The Primer........................................................................................ 3 1.3 PREVIOUS WORK RELATED TO ORGANIC GUN SHOT RESIDUE OR UNFIRED PROPELLANT ANALYSIS........................................................................................ 4 (;3(5,0(17$/......................................................................... 18 2.1 MATERIALS ............................................................................................ 18 2.2 INSTRUMENTATION ................................................................................ 18 2.3 STANDARD PREPARATION....................................................................... 19 2.4 ETHYL ACETATE ALONE PROCEDURE..................................................... 19 2.5 ETHYL ACETATE/DICHLOROMETHANE PROCEDURE............................... 19 2.6 CONSISTENCY OF PROPELLANT COMPOSITION EXPERIMENT ................. 20 2.7 EXCLUSION OF OXYGEN EXPERIMENT .................................................... 20 2.8 TYPE DETERMINATION OF WINCHESTER AMMUNITION ......................... 20 5(68/76$1'',6&866,21 .................................................. 22 3.1 MASS SPECTRA OF UNFIRED PROPELLANT COMPONENTS ....................... 22 The Analysis of Unfired Propellant Particles by Gas Chromatography-Mass Spectrometry: A Forensic Approach Shiona Croft vi 3.1.1 Diphenylamine (C12H11N) ............................................................... 22 3.1.2 Ethyl centralite (C17H20N2O)........................................................... 24 3.1.3 Dibutyl phthalate (C16H22O4) .......................................................... 26 3.2 CONTROLLED STANDARDS ..................................................................... 28 3.2.1 Diphenylamine, ethyl centralite and dibutyl phthalate variation...... 29 3.3 THE ANALYSIS OF PROPELLANT USING ETHYL ACETATE ALONE ........... 30 3.4 REMOVAL OF THE NITROCELLULOSE COMPONENT OF PROPELLANT USING ETHYL ACETATE AND DICHLOROMETHANE........................................................ 44 3.5 CONSISTENCY OF PROPELLANT COMPOSITION FROM A SINGLE BOX/BATCH OF AMMUNITION ............................................................................. 53 3.6 THE EFFECTS OF EXCLUDING OXYGEN ................................................... 58 3.7 TYPE DETERMINATION OF WINCHESTER AMMUNITION......................... 65 3.7.1 Winchester Laser LR HP 2DRM41.................................................. 65 3.7.2 Winchester Expert 23DLH02........................................................... 66 3.7.3 Winchester Winner IDKE52............................................................ 66 3.7.4 Winchester Subsonic LR Rim fire AED1FH31................................. 67 3.7.5 Winchester Superspeed LR HV solid SDSB51.................................. 68 3.7.6 Winchester Superspeed LR HV hollow point 2DRL62...................... 69 &21&/86,216$1')8785(:25.................................. 72 4.1 CONCLUSIONS ........................................................................................ 72 4.2 FUTURE WORK....................................................................................... 73 $33(1',;