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Investigating the Heterogeneous Chemistry of Polycyclic Aromatic Hydrocarbons and Other Organic Species in Atmospheric Aerosols

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Investigating the Heterogeneous Chemistry of Polycyclic Aromatic Hydrocarbons and Other Organic Species in Atmospheric Aerosols University of North Dakota UND Scholarly Commons Theses and Dissertations Theses, Dissertations, and Senior Projects January 2014 Investigating The etH erogeneous Chemistry Of Polycyclic Aromatic Hydrocarbons And Other Organic Species In Atmospheric Aerosols Richard Cochran Follow this and additional works at: https://commons.und.edu/theses Recommended Citation Cochran, Richard, "Investigating The eH terogeneous Chemistry Of Polycyclic Aromatic Hydrocarbons And Other Organic Species In Atmospheric Aerosols" (2014). Theses and Dissertations. 1634. https://commons.und.edu/theses/1634 This Dissertation is brought to you for free and open access by the Theses, Dissertations, and Senior Projects at UND Scholarly Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of UND Scholarly Commons. For more information, please contact [email protected]. INVESTIGATING THE HETEROGENEOUS CHEMISTRY OF POLYCYCLIC AROMATIC HYDROCARBONS AND OTHER ORGANIC SPECIES IN ATMOSPHERIC AEROSOLS by Richard Eugene Cochran Bachelor of Science, University of North Dakota, 2010 A Dissertation Submitted to the Graduate Faculty of the University of North Dakota in partial fulfillment of the requirements for the degree of Doctor of Philosophy Grand Forks, North Dakota December 2014 Copyright 2014 Richard E. Cochran ii iii PERMISSION Title Investigating the Heterogeneous Chemistry of Polycyclic Aromatic Hydrocarbons and Other Organic Species in Atmospheric Aerosols Department Chemistry Degree Doctor of Philosophy In presenting this dissertation in partial fulfillment of the requirements for a graduate degree from the University of North Dakota, I agree that the library of this University shall make it freely available for inspection. I further agree that permission for extensive copying for scholarly purposes may be granted by the professor who supervised my dissertation work or, in her absence, by the Chairperson of the department or the dean of the School of Graduate Studies. It is understood that any copying or publication or other use of this dissertation or part thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of North Dakota in any scholarly use which may be made of any material in my thesis or dissertation. Richard E. Cochran September 29, 2014 iv TABLE OF CONTENTS LIST OF FIGURES ........................................................................................................... xi LIST OF TABLES ........................................................................................................... xiv LIST OF SCHEMES........................................................................................................ xvi ABBREVIATIONS ........................................................................................................ xvii SYMBOLS ....................................................................................................................... xix ACKNOWLEDGMENTS .................................................................................................xx ABSTRACT ..................................................................................................................... xxi CHAPTER 1 ........................................................................................................................1 1. Introduction ..................................................................................................................1 1.1. Atmospheric Aerosols and Particulate Matter ......................................................1 1.2. Sources and Chemical Composition of Atmospheric Aerosols ............................1 1.3. Aging and Fate of Aerosols in the Atmosphere ....................................................2 1.4. Polycyclic Aromatic Hydrocarbons in Atmospheric Aerosols .............................2 1.4.1. Sources and Distribution ................................................................................2 1.4.2. Significance of PAHs .....................................................................................3 1.4.3. Analysis of Polycyclic Aromatic Hydrocarbons............................................4 1.5. Oxidation Products of Polycyclic Aromatic Hydrocarbons in Atmospheric Aerosols ...........................................................................................................................4 1.5.1. Sources and Distribution ................................................................................4 1.5.2. Significance of PAH Oxidation Products ......................................................5 1.5.3. Analytical Methods for Detecting Oxidation Products of PAHs ...................5 1.5.4. Identification of PAH Oxidation Products .....................................................7 1.6. Partitioning of Organic Aerosol Species in the Atmosphere ................................8 v 1.6.1. Theory of Gas-Particle Partitioning ...............................................................8 1.6.2. Influence of the Aerosol Surface on Gas-Particle Partitioning ......................9 1.6.3. Analytical Methods for Defining Matrix-Analyte Interactions .....................9 CHAPTER 2 ......................................................................................................................11 2. SUMMARY AND OBJECTIVES .............................................................................11 CHAPTER 3 ......................................................................................................................16 3. Simultaneous Analysis of Polycyclic Aromatic Hydrocarbons and Their Various Oxidation Products.............................................................................................................16 3.1. Experimental .......................................................................................................16 3.1.1. Materials and Reagents ................................................................................16 3.1.2. Extraction .....................................................................................................18 3.1.3. SPE Fractionation and Preparation for GC analysis ....................................19 3.1.4. GC-MS Analysis ..........................................................................................20 3.1.5. Data Processing ............................................................................................22 3.2. Results and Discussion ........................................................................................23 3.2.1. GC-MS Conditions ......................................................................................23 3.2.2. Limits of Detection and Calibration Parameters ..........................................26 3.2.3. SPE Fractionation ........................................................................................31 3.2.4. Characterization of PM ................................................................................32 3.3. Conclusions .........................................................................................................39 CHAPTER 4 ......................................................................................................................40 4. Extraction of Polycyclic Aromatic Hydrocarbons and Their Oxidation Products Using Pressurized Fluid Extraction. ..................................................................................40 4.1. Experimental .......................................................................................................40 4.1.1. Materials and Reagents ................................................................................40 4.1.2. Extraction .....................................................................................................44 vi 4.1.3. SPE Fractionation and Preparation for GC Analysis ...................................46 4.1.4. GC-MS Analysis ..........................................................................................47 4.1.5. Quantification ..............................................................................................48 4.2. Results & Discussion ..........................................................................................49 4.2.1. Optimization of PFE ....................................................................................49 4.2.2. Comparison of PFE and Soxhlet ..................................................................51 4.2.3. Comparison of PFE to Soxhlet for WS PM .................................................53 4.2.4. Comparing PFE to Soxhlet for Diesel Exhaust PM .....................................58 4.3. Conclusions .........................................................................................................61 CHAPTER 5 ......................................................................................................................62 5. Determination of nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons using atmospheric pressure chemical ionization with high resolution mass spectrometry (APCI-HRMS) .............................................................................................62 5.1. Experimental .......................................................................................................62 5.1.1. Reagents .......................................................................................................62
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