Lightweighting Shipping Containers: Life Cycle Impacts on Multimodal Freight Transportation

This thesis is an exploratory study conducted through Lightweight Innovations for Tomorrow (LIFT) to investigate the energy consumed and greenhouse gases emitted during the multimodal life cycle of a shipping container as well as the potential reductions in environmental burdens for six container lightweighting scenarios. The burdens and savings are reported first for a single shipping container, and then are scaled up to indicate the savings possible if all shipping containers were lightweighted first in the United States and then globally. Additionally, a case study is conducted to examine the environmental burdens associated with several routes possible for the transportation of shipping containers from Shanghai to Detroit, Michigan. This thesis highlights the tradeoff between fuel savings incurred through lightweighting and potential increased production burdens associated with some of the lightweighting strategies. Furthermore, it indicates the influential nature of modal distribution and route selection on life cycle results and demonstrates a specific use of multimodal modeling that could be replicated and applied to other transportation systems. The work presented in this thesis has been recently published in the journal Transportation Research Part D: Transport and the Environment: Buchanan, C. A., Charara, M., Sullivan, J. L., Lewis, G. M., and Keoleian, G. A. (2018). Lightweighting shipping containers: Life cycle impacts on multimodal freight transportation. Transportation Research Part D, 62, 418-432. https://doi.org/10.1016/j.trd.2018.03.011. The thesis contains additional detail related to the methods used.Master of ScienceSchool for Environment and SustainabilityUniversity of Michiganhttps://deepblue.lib.umich.edu/bitstream/2027.42/145427/1/Buchanan_Cailin_Thesis.pd

Hydrodechlorination of Perchloroethylene with Swellable Organically-Modified Silica (SOMS)

Groundwater is an important resource to residential, industrial, and agricultural sectors. Unfortunately, chlorinated compounds such as perchloroethylene and trichloroethylene can contaminate groundwater sources due to heavy industrial use. Current methods of groundwater treatment are costly and slow. In this paper, it is suggested that hydrodechlorination be used as a means to remove chlorinated compounds from groundwater. Current hydrodechlorination efforts, however, are hindered by the deactivating effects of ionic species inherent in groundwater on metal catalysts usually used for hydrodechlorination. It is suggested that if a different support were used for the catalyst rather than the traditional Al2O3 support, the catalyst could be better protected. The suggested material is Swellable Organically-Modified Silica (SOMS). It is expected that the swellable nature of SOMS will increase the number of available sites and the hydrophobic quality of SOMS will help to repel groundwater ionic species. Therefore, in this paper, the hydrodechlorination activity, quantified by percentage of conversion of perchloroethylene, was compared between both fresh and poisoned commercial (1%Pd/Al2O3) and synthesized (1%Pd/SOMS) catalysts. It was determined that when poisoning effects are not considered, the commercial catalyst achieves better conversion, with 95% conversion of perchloroethylene in four hours. When the poisoning effects of NaCl and NaHS are considered, however, the drop in hydrodechlorination activity is significantly more for the commercial catalyst versus the synthesized catalyst. These findings suggest that the SOMS support better protects the Pd when in the presence of poisoning ionic species. IR transmission spectra were also collected for the poisoned catalysts, in order to better understand the effect of the poisons on the surface functional groups. It was determined that sulfur containing species greatly impact the functional group, while the SOMS material better repels the water in the poisoning solutions.A three-year embargo was granted for this item.Academic Major: Chemical Engineerin

Characterizing the Ce3+/Ce4+ Chemistry for Use in Redox Flow Battery Applications

Energy storage technologies will be crucial to meeting rising renewable electricity demand in the U.S., but there is currently not enough storage capacity to meet this demand. As described in Chapter 1, redox flow batteries (RFBs) are a favorable energy storage technology for large scale, long-duration energy storage, but the state-of-the-art all-vanadium RFB (VRFB) is too expensive. Cerium is promising in RFBs because of its higher voltage and cheaper precursor. The economic and environmental performance of a Ce RFB compared to the VRFB has not been assessed in detail, however, and the fundamental processes that control the Ce3+/Ce4+ thermodynamics and kinetics are not understood. To address this, we compare the VRFB and Ce-V RFB storage cost and greenhouse gas (GHG) emissions and study the Ce3+/Ce4+ structures, thermodynamics, and kinetics. The theory behind the economic and environmental modeling and spectroscopy and kinetic measurements is discussed in Chapter 2. In Chapter 3, we develop technoeconomic assessment (TEA) and life cycle inventory (LCI) models and determine that the Ce-V RFB minimum levelized cost of electricity (LCOE) is lower and the two RFBs’ levelized GHG (LGHG) emissions are similar, suggesting Ce should be considered further in RFB applications. The redox potential and exchange current density are identified through a sensitivity analysis to be highly influential to the Ce-V RFB cost and emissions, motivating the need for further work into the fundamental phenomena that control thermodynamics and kinetics. A 194 mV increase in redox potential is equivalent to an increase in kinetics by a factor of two, providing electrolyte and electrode engineering guidance. The Ce3+/Ce4+ redox potential is highly dependent on the electrolyte anion. To determine the link between anions and thermodynamics in Chapter 4, we study the Ce3+ and Ce4+ ionic structures in acids relevant for battery applications. Using UV-Vis spectroscopy, extended X-ray absorption fine structure spectroscopy (EXAFS), and density functional theory calculations, we find that Ce3+ is coordinated by nine water molecules and Ce4+ is complexed by at least one anion. The decrease in redox potential is driven by stronger anion complexation of Ce4+. Thus, to maximize thermodynamics for RFB applications, electrolytes with weaker complexing anions should be selected. The cerium electron transfer kinetics must be increased for RFB applications by optimizing the factors that control kinetics, but the Ce3+/Ce4+ charge transfer mechanism is not known. We couple EXAFS and kinetics measurements to propose a two-step mechanism in H2SO4 (Chapter 5). The first step of the mechanism is a chemical step, and the second step is a rate-determining electron transfer described through Marcus theory. We find the electrolyte controls the kinetics and hypothesize that the Ce3+/Ce4+ kinetics will be fastest in weaker complexing electrolytes, e.g., HClO4. Assuming the same mechanism holds in HClO4 and the preexponential factor does not change, we expect the kinetics can increase by a factor of 10,000 in HClO4, whereas the electrode would affect the kinetics up to a factor of nine through electrostatic effects. To control the kinetics in an RFB, a weaker Ce4+-anion complexing electrolyte like HNO3 should be selected, and the electrode surface area should be increased until the increase in electrode costs outweighs the kinetic savings. Since the electrolyte is expected to control both the Ce RFB’s thermodynamics and kinetics future work should optimize the electrolyte for thermodynamics and kinetics through electrolyte engineering (Chapter 6).PHDChemical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/175660/1/cailinab_1.pd

Unveiling the cerium(III)/(IV) structures and charge transfer mechanism in sulfuric acid

The Ce3+/Ce4+ redox couple has a charge transfer (CT) with extreme asymmetry and a large shift in redox potential depending on electrolyte composition. The redox potential shift and CT behavior are difficult to understand because neither the cerium structures nor the CT mechanism are well understood, limiting efforts to improve the Ce3+/Ce4+ redox kinetics in applications such as energy storage. Herein, we identify the Ce3+ and Ce4+ structures and CT mechanism in sulfuric acid via extended X-ray absorption fine structure spectroscopy (EXAFS), kinetic measurements, and density functional theory (DFT) calculations. We show EXAFS evidence that confirms that Ce3+ is coordinated by nine water molecules and suggests that Ce4+ is complexed by water and three bisulfates in sulfuric acid. Despite the change in complexation within the first coordination shell between Ce3+ and Ce4+, we show that the kinetics are independent of the electrode, suggesting outer-sphere electron-transfer behavior. We identify a two-step mechanism where Ce4+ exchanges the bisulfate anions with water in a chemical step followed by a rate-determining electron transfer step that follows Marcus theory (MT). This mechanism is consistent with all experimentally observed structural and kinetic data. The asymmetry of the Ce3+/Ce4+ CT and the observed shift in the redox potential with acid is explained by the addition of the chemical step in the CT mechanism. The fitted parameters from this rate law qualitatively agree with DFT-predicted free energies and the reorganization energy. The combination of a two-step mechanism with MT should be considered for other metal ion CT reactions whose kinetics have not been appropriately described.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/176715/1/jacsau.2c00484_-_Dylan_Herrera.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/176715/2/annotated-Herrera_Dylan_Design_Expo_-_Dylan_Herrera.pd

Hydrogen Roadmap for the State of Michigan Workshop Report

The Department of Energy (DOE) Office of Clean Energy Demonstrations (OCED) intends to issue a Funding Opportunity Announcement (FOA) entitled “Regional Clean Hydrogen Hubs” (H2Hubs) in collaboration with the Energy Efficiency and Renewable Energy’s (EERE) Hydrogen and Fuel Cell Technologies Office (HFTO) and the DOE Hydrogen Program. The Notice of Intent to release this FOA indicates that the H2Hubs “will form the foundation of a national clean hydrogen network that will contribute substantially to decarbonizing multiple sectors of the economy while also enabling regional and community benefits.” The Bipartisan Infrastructure Law includes $8 billion of funding for this effort and is expected to result in at least four H2Hubs across the U.S. In advance of this announcement, and to identify potential near- and long-term hydrogen deployment opportunities and key enabling factors, the Center for Sustainable Systems (CSS) at the University of Michigan convened the Hydrogen Roadmap for the State of Michigan workshop on May 20, 2022 with support from the Michigan Economic Development Corporation (MEDC) and the University of Michigan Office of Research (UMOR). The CSS research team evaluated hydrogen production, delivery and storage, and end-use application technologies, as well as hydrogen roadmaps and strategy documents from around the world, and presented findings at the Workshop for feedback. The 73 participants at the workshop, who represented commercial, governmental, and academic organizations, also provided input on the location and clustering of Michigan and regional assets related to hydrogen production and use (both current and potential). The information compiled and presented in this Workshop Report is a high-level assessment intended to guide planning and future detailed analysis. A hydrogen ecosystem encompasses production, delivery, storage, and end-use applications, as illustrated in Exhibit ES-1.1 The design of a hydrogen ecosystem for Michigan begins with quantifying the end-use applications for hydrogen, which then defines the demand for production, delivery, and storage of hydrogen. More detailed analysis of demand than is presented here is necessary in order to make decisions on which end uses and production methods should be pursued in Michigan and across the wider region. After characterizing the opportunities and challenges for each hydrogen end-use, production, delivery, and storage technology, we explore their spatial distribution in Michigan and across the Midwest region. Current Michigan and regional assets and potential hydrogen transition industries were compiled and mapped to identify potential hydrogen demand clusters. A summary map is presented as Figure ES-1. The evaluation and spatial mapping of technologies provides the foundation for the hydrogen technology deployment recommendations for Michigan that are presented below.http://deepblue.lib.umich.edu/bitstream/2027.42/191567/1/CSS22-17_MI Hydrogen Roadmap Workshop Report.pdfDescription of CSS22-17_MI Hydrogen Roadmap Workshop Report.pdf : Main ReportSEL