Master of Science, Miami University, 2024, Chemical, Paper and Biomedical Engineering

Engineering microbes for sustainable bioproduction is a promising avenue to tackle problems in pollution, medicine, and energy. Traditional model organisms have received much attention due to their easily manipulated genetics and well characterized growth. However, there are a wealth of non-model microbes with attributes that are beneficial for biotechnological applications, but genetic tools must first be developed to engineer them by incorporating foreign DNA and characterizing bioparts for controlled expression. In this work, we are looking to expand the genetic toolbox for an environmental-isolate of Priestia megaterium, called SR7, that can survive under high pressures of CO2. Bioprocessing under high pressures of CO2 is expected to simultaneously create an aseptic culture environment as well as extract bioproducts as they are formed, both benefits for continuous bioproduction. An enhanced transformation method was developed, permitting bioparts characterization. We have compared promoters, origins of replication, and antibiotic resistance genes between two plasmid architectures. We identified three functional Gram-positive origins of replication for SR7. Three plasmids were verified to have enhanced recombinant protein production compared to a previously used plasmid.

Committee: Jason Boock (Advisor); D.J. Ferguson (Committee Member); Jason Berberich (Committee Member) Subjects: Biology; Chemical Engineering; Microbiology; Molecular Biology

Doctor of Philosophy, The Ohio State University, 2023, Animal Sciences

The finite nature of natural gas, in addition to environmental and health issues arising from the burning of fossil fuels, have propelled increased interest in the development of renewable and clean alternative energy sources. Biofuels, and specifically, biobutanol production through ABE fermentation is a promising means of achieving the goal of replacing fossil fuels with a renewable energy source in the short term. However, the low yield and productivity of the butanol-producing fermentation workhorse, Clostridium beijerinckii, is a major impediment to the commercialization of biobutanol production. Extensive metabolic engineering efforts have been made to generate an industrially applicable strain; however, success has been limited. The large genome, complex metabolic and regulatory networks, and the abundance of hypothetical proteins in C. beijerinckii, in addition to the limited success obtained with metabolic engineering efforts, indicate there could be new unidentified butanol production determinants in C. beijerinckii. Therefore, this study explored the use of a ribozyme-based approach as a reverse genetics tool to identify unknown genetic determinants of butanol production in C. beijerinckii. Using Gibson assembly, the Escherichia coli-Clostridium shuttle plasmid carrying the E. coli RNase P (M1 RNA) sequence and syntheized external guide sequences (GS) were assembled, to generate a plasmid library of customized M1-based ribozyme-guide sequence (GS) constructs. The M1GS library was generated to target 31 genes that code for hypothetical proteins, which are among the 100 most expressed genes during the transition from acidogenesis to solventogenesis in C. beijerinckii. Generated customized M1GS plasmid library was used to transform C. beijerinckii to generate individual transformants with targeted mRNA degradation. With selective (antibiotics) medium, high performance liquid chromatography and spectrophotometric assays, transformants with various growth and (open full item for complete abstract)

Committee: Thaddeus Ezeji (Advisor); Victor Ujor (Committee Member); Zhongtang Yu (Committee Member); MacDonald Wick (Committee Member); Lisa Bielke (Committee Member) Subjects: Alternative Energy; Animal Sciences; Biochemistry; Molecular Biology

Master of Science, The Ohio State University, 2020, Environment and Natural Resources

Research on dedicated biofuel crops has typically focused on increasing yields and soil carbon sequestration. What is seldom studied is how biofuel crops affect the soil they are grown on. Soil is responsible for influencing important ecosystem services such as carbon sequestration, erosion control, and root development. Three biofuel crops, no-till corn (Zea mays), switchgrass (Panicum virgatum), and miscanthus (Miscanthus giganteus), were selected to examine their influence on soil physical and hydrological properties at three different depths (0 – 10 cm, 10 – 20 cm, and 20 – 40 cm). The goal of our study was to determine whether biofuel crops could improve soil physical and hydrological properties. The field study was conducted in Columbus, OH, on a biofuel research plot 7 years after establishment. A total of 36 bulk samples and 36 soil cores were collected. Miscanthus produced significantly higher yields (16.0 Mg ha-1) than both switchgrass (10.1 Mg ha-1) and corn (4.54 Mg ha-1) following a mid-season harvest. No-till corn produced the lowest yields because of the late seeding and poor crop stand. However, corn did not grow to maturity so the field was left to fallow. Significant differences in soil physical properties only occurred within the top 10 cm. Bulk density under miscanthus (1.39 Mg m-3) was significantly lower compared to both switchgrass (1.51 Mg m-3) and no-till corn (1.53 Mg m-3). There were no significant differences in calculated porosity and % water-stable aggregates. Mean weight diameter and geometric mean diameter were significantly higher under no-till corn (4.77 mm & 1.71 mm) and switchgrass (5.00 mm & 1.79 mm) compared to miscanthus (3.39 mm & 1.32 mm). The aggregate distribution revealed the same trend after wet-sieving, miscanthus retained significantly fewer aggregates larger than 4.75 mm compared to the other crops. When compared to a previous study conducted on the same plots in 2013, bulk density decreased under miscanthus at depth 0 (open full item for complete abstract)

Committee: Rattan Lal PhD (Advisor); Christine Sprunger PhD (Committee Member); Scott Demyan PhD (Committee Member) Subjects: Soil Sciences

Master of Science (MS), Ohio University, 2018, Environmental Studies (Voinovich)

Bioenergy could help reduce CO2 emissions from agriculture that contribute to climate change, while at the same time supply energy to a growing population. Varying levels of inputs within bioenergy crop fields, such as pesticide use or annual tilling, can impact arthropod biodiversity and abundance. The research presented here examines the impact of habitat type (Miscanthus x giganteus, Panicum virgatum, abandoned agriculture, and forested edge) on the diversity and abundance of arthropods in small (The Ridges Land Lab) and larger (The Wilds) planted plots in southeastern Ohio. A variety of collection methods (sweep nets, flight traps, and Berlese funnels) were used over a three month period to collect arthropods from different trophic groups. Overall, 25,390 arthropods were captured with the highest abundance consistently seen in forested edge habitats, followed by abandoned agriculture, switchgrass, and lastly miscanthus. Flying insects found in the forested edge were three fold more abundant than those found in miscanthus plots, with intermediate levels in switchgrass and abandoned agriculture. Dominant flying arthropod groups included leaf hoppers, flies and rove beetles. Abundance of litter arthropods was almost two fold higher in switchgrass than in miscanthus plots: dominant taxa included oribatid mites, ants, ground beetles, and collembolans. Taxonomic richness and Shannon diversity were lower in litter samples compared to flight/ sweep samples. Compared to forested edges, miscanthus supported fewer omnivores, pollinators, and predator/parasites. Detritivorous arthropod abundances did not differ across habitat types. No significant differences were noted between arthropod diversity and abundance between the larger fields of biofuel grasses at the Wilds compared to the Ridges Land Lab. This current study shows that cellulosic ethanol crop type does have an impact on arthropod communities; with miscanthus consistently supporting the least diverse and lowest ar (open full item for complete abstract)

Committee: Kelly Johnson (Committee Chair); Sarah Davis (Committee Member); Arthur Trese (Committee Member) Subjects: Agriculture; Alternative Energy; Entomology; Environmental Studies

Doctor of Philosophy (PhD), Ohio University, 2016, Civil Engineering (Engineering and Technology)

Microalgae cultivation has gained considerable interest recently as a potential source for the production of biofuels. Nevertheless, many obstacles still face the industrial application of microalgal biofuels such as the high production costs due to nutrient requirements and the high energy input for cultivating and harvesting the microalgal biomass. In this study, the utilization of the anaerobic digestate as a nutrient medium for the cultivation of two microalgal species was investigated. The anaerobic digestate was initially characterized and several pretreatment methods such as hydrogen peroxide treatment, filtration using polyester filter bags, and supernatant extraction were applied to the digestate. It was found that the supernatant extraction was the simplest and most effective method in decreasing the turbidity and COD of the diluted anaerobic digestate while maintaining sufficient nutrients (particularly nitrogen) for microalgae cultivation. The microalga Neochloris oleoabundans was cultivated using the diluted anaerobic digestate supernatant on a bench-scale. It was found that 100 mg N/L dilution was sufficient to maximize the biomass concentration of this microalga. It was attempted to scale up the cultivation of the microalga N. oleoabundans to 100 L raceway ponds; however, the culture was contaminated with other algal species. The microalga Scenedesmus dimorphus was then cultivated using the anaerobic digestate supernatant on a bench-scale. The highest biomass concentration recorded was 654 mg/L. Furthermore, it was found that 50 – 100 mg N/L dilutions were sufficient to maximize the specific growth rate of this microalga while still producing relatively high biomass concentrations. As a result, the microalgae cultivation was scaled up to 100 L raceway ponds using 100 mg N/L dilution at 454 and 317 µmol/m2/s light intensities and 50 mg N/L dilution at 384 and 234 µmol/m2/s light intensities. The highest biomass concentration achieved was 432 mg/L in (open full item for complete abstract)

Committee: R. Guy Riefler (Advisor) Subjects: Civil Engineering; Environmental Engineering

Master of Science, The Ohio State University, 2015, Evolution, Ecology and Organismal Biology

Miscanthus sinensis is a perennial, ornamental grass from Asia that has been cultivated in North America for over a century. Miscanthus sinensis has become naturalized (“feral”) in at least 23 states, and the 3x variety is currently a leading perennial grass biofuel crop. The long-term success of cultivating Miscanthus for biofuels hinges on how to avoid and mitigate inadvertent production of invasive biotypes. Miscanthus x giganteus is a widely grown sterile triploid hybrid, but there are fertile hybrids such as `Powercane'. To gain insight into the competitive ability of these taxa, we established a competition experiment. The experiment includes three feral accessions of M. sinensis from Ohio and West Virginia, a horticultural variety of M. sinensis, and M. x giganteus `Powercane'. Competition treatments consisted of surrounding focal Miscanthus biotypes with three individuals of native Panicum virgatum (Switchgrass), non-native Bromus inermis (Bromegrass), or no competitors. Plots were monitored for two growing seasons. We found significant differences among Miscanthus biotypes, and with competition, but no significant interaction. Miscanthus x giganteus `Powercane' produced significantly more dry biomass and larger basal area than two of the three feral populations. The response to competition was highly significant, but there were no significant differences between native and non-native competitors. These results suggest variation among Miscanthus biotypes can influence competitive outcomes and performance. In conclusion, M. x giganteus exhibited superior performance but produced few seeds, which might limit its potential to escape cultivation and establish feral populations.

Committee: Maria Miriti Ph D. (Advisor); Allison Snow Ph. D. (Committee Member) Subjects: Agriculture; Ecology; Environmental Studies

Master of Science in Chemical Engineering, Cleveland State University, 2015, Washkewicz College of Engineering

With recent concerns over the environmental implications of burning fossil fuels coupled with the depletion of fossil fuel reserves an alternative source of energy is needed. Algae derived biofuels may be an effective replacement for transportation fuels as they are carbon neutral and have a high area productivity. Algae is superior to terrestrial plants as a biofuel source due to its high oil productivity and efficiency along with the fact that it will not displace food production. Currently the largest obstacle to the implementation of commercial algae to biofuel processes is algae dewatering. The separation of algae from water is difficult due to the dilute concentration of the algae suspension and the extremely low settling velocity of the algae biomass. This work investigates recent improvements to the downward flow inclined gravity settler which has the potential to unlock this much needed process. Additionally, an investigation into algae settling velocity, a field which has received little attention, is also discussed.

Committee: Joanne Belovich PhD (Advisor); Jorge Gatica PhD (Committee Member); Moo-Yeal Lee PhD (Committee Member) Subjects: Chemical Engineering

Master of Science, The Ohio State University, 2014, Food, Agricultural and Biological Engineering

Microalgae have been extensively studied for their capabilities in producing more lipids per acre than agricultural crops. Because of high costs, this technology has yet been proven economical on a large scale. Currently unreported is the use of flowback water from shale gas exploration as a way to reduce costs by meeting the water demand of marine microalgae cultivation. Additionally, while anaerobic digestion (AD) effluent has been shown as a promising alternative nutrient source for microalgae cultivation, unreported is the use of AD effluent as a nutrient supplement for the cultivation with flowback water. This study hypothesized that the combination of the flowback water, as the source of water, and the AD effluent, as the source of nutrients, may act as a growth medium for marine microalgae cultivation. To validate this hypothesis, three marine microalgal strains were evaluated on the ability to adapt to different concentrations of the AD effluent in the flowback water. Among the microalgal candidates, it was determined that Nannochloropsis salina and Dunaliella tertiolecta, microalgal strains previously considered as candidates for biofuels and pigment production, were the most tolerant to the inhibitors found in the flowback water and the AD effluent. These microalgal strains were found to achieve the highest average biomass productivity in the medium composed of the flowback water supplemented with the AD effluent loading of 6%. Algal growth in this medium was then compared to growth in a medium composed of commercial nutrients and salts at similar initial inorganic nitrogen (~132 mg L-1 N), salinity (~42 g L-1), and pH (~7.97) levels. Comparable growth in both media was found with the specific growth rates of 0.293 and 0.348 day-1 and the average biomass productivities of 225 and 275 mg L-1 day-1for N. salina and D. tertiolecta, respectively. Analysis of the lipid content and profile of both strains cultivated in the medium composed of the flowback (open full item for complete abstract)

Committee: Yebo Li (Advisor); Peter Ling (Committee Member); Jiyoung Lee (Committee Member) Subjects: Agricultural Engineering

Doctor of Philosophy, The Ohio State University, 2014, Molecular, Cellular and Developmental Biology

Recently, with the concerns of unstable crude oil supply, rapid increase in gasoline prices and severe climate changes, higher alcohols (alcohols with more than two carbons) have gained interests for their potentials in replacing petroleum as new generation transportation fuels. Among all these candidates, n-butanol as a four carbon solvent has received the most attention because it shares very similar characteristics with gasoline and can be naturally produced by solventogenic Clostridia via Acetone-Butanol-Ethanol (ABE) fermentation. However, butanol production by these native producers suffers from low titer and yield due to inefficient substrate conversion and butanol cytotoxicity upon cell growth and metabolism. Also, the necessity of generating byproducts during fermentation significantly reduces butanol titer and product selectivity, and therefore, increases the cost for butanol recovery through distillation. In order to commercialize biobutanol as economically as petroleum-based processes, a more optimized overall fermentation strategy is highly desirable. Therefore, the goal of this study was to establish cost-effective fermentation processes for higher alcohols production through various approaches, including inexpensive feedstock utilization, process optimization employing external driving forces, and new strain development. First, the stability of hyper-butanol-producing strain Clostridium acetobutylicum JB200 was validated by long-term repeated batch fermentation with cells immobilized in a fibrous bed bioreactor using sucrose as substrate. Its stable fermentation performance using low-cost sugarcane juice with a high butanol titer (16—20 g/L), yield (~0.21 g/g sucrose) and productivity (~0.32 g/L•h) indicated that JB200 is a promising strain for industrial application. Then, the effect of extra driving forces provided by artificial electron carrier addition on butanol production by metabolically engineered Clostridium tyrobutyricum strain CtΔack-adhE2 (open full item for complete abstract)

Committee: Shang-Tian Yang Dr. (Advisor); Jeffrey Chalmers Dr. (Committee Member); Robert Tabita Dr. (Committee Member); Robert Lee Dr. (Committee Member) Subjects: Chemical Engineering

Master of Science, The Ohio State University, 2013, Food, Agricultural and Biological Engineering

Concerns about unsustainable fossil energy use have led to increased research and development for cost-effective and renewable transportation fuels. Microalgae have gained considerable interest as a biofuel feedstock due to their ability to be grown in areas unsuitable for crops, high growth rates and high oil content. However, massive commercial nutrient and freshwater requirement in open raceway pond cultivations have drawn concerns regarding the economic sustainability of the microalgae to biofuel process, prompting research towards culturing microalgae with nutrients from freely available wastewater streams. Anaerobic digestion (AD) is an organic waste treatment process that utilizes microorganisms to produce biogas for renewable energy. Digested liquor from AD, or AD effluent, is rich in nitrogen and phosphorus. To reduce nitrogen and phosphorus runoff, research has been conducted to culture microalgae with diluted AD effluent for nutrient removal and lipid-rich biomass production. Most previous research cultured freshwater algae strains with diluted AD effluent. However, to reduce freshwater consumption, attention should be focused on culturing marine strains with AD effluent as a nutrient source. Culturing any microalgae strain requires analysis of the effects of seasonal climatic conditions on growth prior to scale-up in open raceway ponds. Collection of these data will improve prediction of biomass and lipid productivity in realistic outdoor cultivations. However, some factors encountered in outdoor systems are difficult to simulate in laboratory settings. Evaluation of the effects of predator contamination on biomass, lipid, and fatty acid production is required for prediction of biofuel yield. Finally, economic analyses are critical to evaluate future research opportunities that can improve the microalgae to biofuel process. In this study, specific growth rate, biomass productivity, total nitrogen (TN) removal, lipid and fatty acid content of Na (open full item for complete abstract)

Committee: Yebo Li PhD (Advisor); Peter Ling PhD (Committee Member); Brian McSpadden Gardener PhD (Committee Member) Subjects: Agricultural Engineering

Doctor of Philosophy, The Ohio State University, 2012, Agricultural, Environmental and Developmental Economics

In this dissertation, a framework for modeling technological, economic, environmental, and social impacts over the life cycle of ten transportation fuels is developed. This is accomplished by linking engineering-based life cycle analysis of the fuels with choice analysis techniques for eliciting and understanding social preferences for multi-attribute consumption vectors. The use of life cycle data allows for a unique accounting of a broad range of environmental, natural resource, and health effects over the entire production and consumption life cycle of each transportation fuel. Combining these life cycle and stated choice analyses allows for social preferences to be established for the externalities resulting from the use of the different transportation fuels. This results in a unique model allowing for improved valuation of alternative fuel options and fuel policy design. The analysis is extended through the estimation of individual level preference parameters; allowing parameter, marginal price and total willingness-to-pay distributions to be derived from the individual level estimates. This creates a unique opportunity to test restrictions associated with traditional logit models used in discrete choice and welfare analysis, as well as compare parameter and welfare results across the two modeling frameworks.

Committee: Timothy Haab PhD (Committee Chair); Brent Sohngen PhD (Committee Member); H. Allen Klaiber PhD (Committee Member) Subjects: Energy; Environmental Economics

Master of Science, The Ohio State University, 2009, Environmental Science

The Conservation Reserve Program (CRP) was established by the Food SecurityAct of 1985 to pay farmers to retire highly erodible and environmentally sensitive cropland and pasture from production. These retired lands have been under increased pressure for conversion to row crops given the relatively high crop prices that have prevailed until recent months. This thesis compared CRP land to row crop production using three methods financial analysis, economic analysis, and emergy evaluation. This project also considered the possibility of using CRP land for bioenergy production in Ohio and considered how much farmers would need to be paid for their biomass to make harvesting a financially optimal choice. A financial analysis was carried out to determine which factors would have the greatest influence on whether farmers will put conservation land back into production. The analyses showed that with high corn and soybean prices, $5.25 and $13.30 per bushel respectively, crop production almost always had higher returns than CRP. However, under lower crop prices, $3.25 and $7.70 per bushel respectively, CRP land always had a higher return. To address the economic value of CRP crop production, this analysis considered the benefits and costs to society of having land enrolled in either system. The results of this analysis show the economic value of average productivity CRP land to be -$19.01 per acre per year. This means the cost of CRP to society is greater than its benefits. However, CRP is still economically superior to crop production, except under the highest crop prices considered. Emergy evaluation was used to compare the sustainability of CRP land and crop production (corn and soybeans) using an ecologically based methodology. CRP land was shown to be more sustainable than corn and soybean production due to its reliance on renewable inputs. The study also suggested that incoming soil erosion and water runoff from adjoining fields are two of the most important inputs to (open full item for complete abstract)

Committee: Fredrick Hitzhusen PhD (Advisor); David Barker PhD (Committee Member); Frederick Michel PhD (Committee Member) Subjects: Agriculture; Economics; Environmental Science

Master of Science (MS), Ohio University, 2010, Chemical Engineering (Engineering and Technology)

In the production of cellulosic ethanol, the pretreatment of biomass step is considered the most expensive and difficult part of the process. In Supercritical CO2 (SC-CO2) pretreatment method, CO2, which is considered a green solvent is used to treat the biomass. In this work corn stover, switchgrass and rye straw were pretreated using the SC-CO2 at various temperatures and pressures and subsequently enzyme hydrolyzed using the cellulase enzyme. The samples were analyzed for the presence of glucose. A typical CO2 to biomass ratio of 5/50 (g/g) was used in tests. Biomass samples were wetted with water prior to the SC-CO2 treatment. CO2 pressure was released as quickly as possible by opening a quick release value. For all pretreatments glucose yields from corn stover was higher than untreated samples (12mg/100mg biomass) and the maximum glucose yield (30mg/100mg biomass) was found at 3500psi and 150°C. These conditions were chosen for the pretreatment of various other biomasses. The maximum glucose yield for untreated switchgrass and rye straw were found to be 12mg/100mg biomass and 7.6mg/100mg biomass, respectively. The pretreated switchgrass (14mg/100mg of biomass) showed no improvement in the glucose yield as compared to an untreated sample. However, the pretreated corn stover (30mg/100mg biomass) and rye straw (13.5mg/100mg biomass) showed threefold and twofold increase, respectively. The SC-CO2 pretreatment with addition of catalysts such as H2SO4 and HCl was studied on rye straw. The addition of H2SO4 and HCl to the SC-CO2 pretreatment both improved the glucose yield as compared with the SC-CO2 pretreatment. The X-Ray diffraction result showed that there was no change in crystallinity of the SC-CO2 treated corn stover when compared to the untreated. SEM results showed the changes in surface morphology of the SC-CO2 treated corn stover when compared with untreated corn stover. This shows that the increase in glucose yield from enzyme hydrolysis for the SC-CO2 tre (open full item for complete abstract)

Committee: Tingyue Gu PhD (Advisor); Douglas Goetz PhD (Committee Co-Chair); Ahmed Faik PhD (Committee Member); Ben Stuart PhD (Committee Member) Subjects: Chemical Engineering

Master of Science (MS), Ohio University, 2008, Environmental Studies (Arts and Sciences)

The increased interest in renewable biofuels, such as biodiesel and ethanol, has come in the wake of higher domestic fuel costs after many years of low consumer prices. With the increase in the price of petroleum-based fuels and growing concern over the reliance on foreign oil from unstable parts of the world there has been more interest to look for cheaper, more sustainable energy resources. While domestically produced sustainable energy sources have the potential to spur growth for domestic farming communities, they have also been touted as being more environmentally friendly. There is also discussion about the potential for biofuels powering a large number of vehicles for the United States transportation sector while producing lower emissions and greenhouse gases. Some see this as a way to help reduce the effects of global warming but issues such as the availability of limited feedstock to produce the biofuels and bigger pictures such as food versus fuel are also a growing concern. There are technical drawbacks to biofuels such as decrease in power, solvency issues, public perception, price competitiveness, feedstock availability, the waste stream produced and whether or not this waste can be dealt with in a sustainable manner. There are also issues related to the net energy gain from producing biofuels, which must also be addressed. In terms of acres harvested, Ohio is one of the top ten agricultural states in the country and produces significant amounts of corn and soybeans, the main feedstock for biofuels. Many view biofuels as a way to stimulate the state economy while producing a more environmentally friendly domestic fuel. With new alternative fuels there are certain challenges in order to make these fuels more widely available. In this thesis I will explore the challenges of biofuels from the perspective of small-scale producers in Ohio that have a production rate of less than 5 million gallons per year.

Committee: Michele Morrone (Advisor) Subjects: Environmental Sciences

Master of Science (M.S.), University of Dayton, 2012, Chemical Engineering

Synthetic fuel, which is generated from syngas via Fischer – Tropsch synthesis, provides the world with an alternative for conventional fossil energy resources. Generating syngas is a prerequisite and critical for Fischer – Tropsch synthesis. The conventional route from biomass to synthetic fuel uses gasification to produce syngas. This route requires oxygen, which increases the cost of the process. In contrast, anaerobic digestion takes place in the absence of oxygen, which might be more economically favorable. This thesis models and simulates a possible process of generating syngas from biomass: anaerobic digestion on an industrial scale, and to compare the economics and feasibility of this approach with conventional gasification.

Committee: Amy Ciric phD (Committee Chair); Scott Gold phD (Committee Member); Michael Elsass phD (Committee Member) Subjects: Chemical Engineering

Master of Sciences, Case Western Reserve University, 2009, Physics

It is shown that a lateral displacement array is technically and commercially feasible for the dewatering of microalgae for the production of algal oil for energy. Process economics of algal oil are examined for dewatering process target cost. Device requirements and the underlying physics of the technology are investigated. Technical feasibility is evaluated for real world operation, scale-up, and manufacturability. Designs are proposed for cost reduction based on underlying theory and manufacturability. Multiple manufacturing methods are evaluated, ranked for technology readiness level and manufacturing readiness level, and cost of goods sold. A gravity-fed unit manufactured with the hot embossing method is recommended for full scale production and is shown to have a total cost reduction of 67% to the economic threshold of $5 per barrel of oil.

Committee: Brown Robert PhD (Committee Chair); Taylor Cyrus PhD (Committee Member); Berner J. Kevin PhD (Committee Member); Lane Christopher PhD (Committee Member); Caner Edward (Committee Member) Subjects: Energy; Engineering; Fluid Dynamics; Physics

Master of Science in Engineering, Youngstown State University, 2013, Department of Civil/Environmental and Chemical Engineering

The process of extracting sugars from cellulosic materials in a high pressure and high temperature reactor was studied to maximize the production of sugars to use in the butanol fermentation process. The addition of chemicals was not used in this study; the components were wood based and water. The wood based materials used in the laboratory research were maple and sycamore. The research consisted of maximizing the amount of dissolved cellulosic material, by comparing the types of woods dissolved, comparing the temperatures and time at which the cellulosic material was dissolved, and recycling the liquor to maximize the amount of dissolved material. The laboratory research showed that the optimum combination of time and temperature needed to obtain the optimum dissolved material was 60 minutes at 250°C. It was also concluded that by recycling the liquor, the total dissolved solids for the three extraction runs was 18.85 grams, 53.96% of the solids were dissolved into the liquor.

Committee: Douglas Price PhD (Advisor); Scott Martin PhD (Committee Member); David Kurtanich PE (Committee Member) Subjects: Chemical Engineering; Environmental Engineering

Doctor of Philosophy in Engineering, University of Toledo, 2012, Chemical Engineering

Constantly growing world population leads to ever-increasing energy demand and is stretching the available energy supplies. Consequently, new energy sources must be identified and developed. Economic, environmental and social impact must be considered when evaluating alternative energy sources. An ideal source would be locally distributed and renewable with minimal economic and environmental impact on our current lifestyle. Membrane processes have gained importance in a wide spectrum of applications due to their low energy requirements. Process technologies for alternative energy production can be intensified with the application of membranes. This dissertation is focused on the application of membrane science for advancing the efforts to develop sustainable energy alternatives. We developed two membrane processes, one for application in a bio-refinery based on ligno-cellulosic biomass and another for electricity generation from salinity gradient. The first process development attempts to solve a separation issue related to a bio-refinery that operates with a ligno-cellulosic biomass feedstock. Production of bio-ethanol from ligno-cellulosic biomass requires pretreatment of the biomass to hydrolyze hemi-cellulose, separate lignin and reduce cellulose crystallinity. During the pretreatment by dilute acid hydrolysis (or other method of hydrolysis), several grams of acetic acid per liter of hydrolysate are generated. Acetic acid needs to be removed from the hydrolysate since it can dramatically reduce the efficiency of the subsequent fermentation step by inhibiting enzyme activity. The conventional method of hydrolysate detoxification, lime treatment, consumes significant quantities of calcium hydroxide, involves solids handling and does not produce any valuable products. We propose to remove the acetic acid with an alternative process whereby acetic acid is extracted into 1-octanol in a membrane extractor and is reacted with 1-octanol in situ with a catalyst present o (open full item for complete abstract)

Committee: Glenn Lipscomb (Committee Chair); Maria Coleman (Committee Member); Ronald Fournier (Committee Member); Dong-Shik Kim (Committee Member); Sasidhar Varanasi (Committee Member) Subjects: Chemical Engineering; Energy; Engineering; Sustainability