You are here

Characterization of Interfacial Material Isolated from Petroleum Crude Oils by FT-ICR MS

Title: Characterization of Interfacial Material Isolated from Petroleum Crude Oils by FT-ICR MS.
191 views
20 downloads
Name(s): Clingenpeel, Amy, author
Marshall, Alan G. (Alan George), professor directing dissertation
Landing, William M., university representative
Dorsey, John G., committee member
Dalal, Naresh S., committee member
Rodgers, Ryan P., committee member
Florida State University, degree granting institution
College of Arts and Sciences, degree granting college
Department of Chemistry and Biochemistry, degree granting department
Type of Resource: text
Genre: Text
Issuance: monographic
Date Issued: 2015
Publisher: Florida State University
Florida State University
Place of Publication: Tallahassee, Florida
Physical Form: computer
online resource
Extent: 1 online resource (105 pages)
Language(s): English
Abstract/Description: As the global supply of easily accessible, light crude oil diminishes, production of heavy crude oils and offshore drilling for light crude oils will continue to increase. However, one problem that is often encountered during the production of these heavy and subsea crude oils is the formation of stable water-in-oil (W/O) or oil-in-water (O/W) emulsions. Although emulsions may be intentionally formed during the recovery of heavy crude oils, emulsions must be broken before the crude oil is refined. If left untreated, these emulsions may contribute to severe corrosion issues (due to entrained salt) and equipment failure. In the case of subsea crude oils, stable W/O emulsions may be encountered if the crude oil enters the environment (e.g. Deepwater Horizon oil spill). The emulsions encountered here reduce the effectiveness of remediation efforts (e.g. skim boats used to remove crude oil from the environment) and slow recovery efforts. Therefore, a key objective in petroleum production is to understand what types of species contribute to stable emulsions in order to determine how to best treat such undesirable emulsions. Emulsion stability is controlled by the surface-active characteristics of a small fraction of compounds that exist or are added to the crude oil matrix. Collectively, these species generate a molecular layer at the oil/water interface which stabilizes the emulsion by resisting drainage and hence coalescence between dispersed droplets. Characterization of these compounds has been hindered by carryover issues from the whole crude oil. However, a novel method for the isolation of these surface-active compounds which minimizes carryover issues was recently introduced. Here, this "wet silica" method is used to isolate interfacially active material from petroleum crude oils. The method is modified (e.g. vary water loading, vary water pH) in order to understand what types of species partition to the oil/water interface under each condition through characterization by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The method is also used to isolate IM from a variety of different crude oil samples (e.g. fractionated crude oil, weathered crude oils, etc.) to determine which fractions and types of compounds contribute most to stable emulsions. Chapter one presents background information on petroleum crude oils, petroleum emulsions, and the "wet silica" method necessary for understanding the data presented in chapters three through nine. Information on the techniques (electrospray ionization (ESI), FT-ICR MS) used to characterize isolated IM are later described in chapter two. Modifications to the "wet silica" method are described in chapters three and four: chapter three examines the role of water content adsorbed to silica gel for the selective isolation of interfacially active material from Athabasca bitumen while chapter four explores how varying water pH affects the composition of isolated IM from Athabasca bitumen. Chapters five and six examine how different IM fractions contribute to the overall Athabasca bitumen emulsion stability. Chapter five explores how isolated IM water-soluble organics differ in composition and stability characteristics compared to the oil-soluble IM fraction. Here, IM water-soluble organics are observed to generate stable emulsions. However, asphaltenes alone are generally believed to play the most significant role in emulsion stability. Therefore, in order to understand the contributions of asphaltenes to isolated IM, chapter six systematically explores the contributions of the asphaltene and maltene fractions of Athabasca bitumen to the IM isolated from the whole crude oil. Yet, previous studies have suggested that rearrangement occurs at the interface over time. Therefore, chapter seven characterizes the species that move to the oil/water interface once the most surface active Athabasca bitumen compounds are depleted. While differences are observed in the IM isolated from the different Athabasca bitumen fractions presented in chapters seven and eight, it is possible that low-molecular weight acids in the IM samples preferentially ionize and hinder the detection of high-molecular weight acids and asphaltene species in the IM fraction of these samples. In order to determine if low-molecular weight acids are preferentially ionized, chapter eight examines how the compositional space coverage of species isolated in 9 different IM acid fractions (separated by hydrophobicity) from the whole Athabasca bitumen compare. In contrast to the work performed on heavy crude oils in chapters three through eight, Chapter 9 characterizes IM isolated from a light crude oil. Here, IM is isolated from a variety of different Deepwater Horizon crude oils samples (i.e. whole crude, photochemically weathered, environmentally weathered) in order to gain insight into the degradation pathways (abiotic, biotic) of IM compounds in the environment. Finally, chapter ten details future work that will be performed to gain further insight into the structure and type of species which contribute most to emulsion stability under a range of conditions.
Identifier: FSU_2016SP_Clingenpeel_fsu_0071E_12846 (IID)
Submitted Note: A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy.
Degree Awarded: Fall Semester 2015.
Date of Defense: December 2, 2015.
Keywords: Asphaltenes, Bitumen, Emulsion, FT-ICR, ICR, Interfacial Material
Bibliography Note: Includes bibliographical references.
Advisory Committee: Alan G. Marshall, Professor Directing Dissertation; William M. Landing, University Representative; John G. Dorsey, Committee Member; Naresh S. Dalal, Committee Member; Ryan P. Rodgers, Committee Member.
Subject(s): Chemistry
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_2016SP_Clingenpeel_fsu_0071E_12846
Use and Reproduction: This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). The copyright in theses and dissertations completed at Florida State University is held by the students who author them.
Host Institution: FSU

Choose the citation style.
Clingenpeel, A. (2015). Characterization of Interfacial Material Isolated from Petroleum Crude Oils by FT-ICR MS. Retrieved from http://purl.flvc.org/fsu/fd/FSU_2016SP_Clingenpeel_fsu_0071E_12846