Engineering Commons^™

Enhanced Co2 Conversion By The Simultaneous Doping Of Co, Fe, And Mn In The B-Site Of A Lanthanum Perovskite, Adela E. Ramos

USF Tampa Graduate Theses and Dissertations

There is a pressing need for carbon dioxide (CO₂) mitigation technologies as increasing emissions continue to threaten our environment. Carbon capture and storage (CCS) alone would not be able to achieve temperature rise below 2 °C. In addition, CCS cost increases considerably for power generation and other industries where CO₂ separation is necessary. Conversion of CO₂ to usable products is the most economical and feasible solution as it could offset CO₂ separation cost. Liquid fuels are an attractive route since it is a commodity used globally and demand increases with population and economic growth. Conversion …

Sorption Of Benzene, Toluene And Ethylbenzene By Plasticized Poly (Ethyl Methacrylate) Using Quartz Crystal Microbalance At 298.15k, Kiranpreet Kaur

USF Tampa Graduate Theses and Dissertations

Quartz crystal microbalances (QCM) are chemical sensors used for liquid and vapor sensing. In this thesis work, plasticized poly (ethyl methacrylate) (PEMA) coated QCM was used to study sorption behavior of benzene, ethylbenzene and toluene in respective polymer at 298.15K. Poly (ethyl methacrylate) (PEMA) is a promising polymer with solubility parameter close to BTEX compounds, but it's glassy and rigid nature at room temperature make it less sensitive. The addition of plasticizers (Diisononyl cyclohexane-1,2-dicarboxylate (DINCH) and Diisooctyl azelate (DIOA)) lowers the glass transition temperature, provides flexibility and thus increases the free volume of the polymer to enhance analyte sorption. In …

Effect Of Heating On Heat Capacity Of Vegetable Oils Used For Biofuel Production, Sailee Nitin Nagpurkar

USF Tampa Graduate Theses and Dissertations

Biodiesel has become a major renewable fuel for diesel engines particularly from various waste sources. New biodiesel production technologies are emerging with data demands for efficient process design. This project highlights the data requirements, gaps in the thermo-physical property data, and consolidation of experimental and estimation methods for effective process development. Knowing the thermodynamic properties of a substance is important in order to know what process or procedures it has to go under. The aim of this project is to assess the potential of vegetable oils to serve as feedstock for biofuel production by determining their heat capacity (Cp). Such …

Photocatalytic Carbon Dioxide Conversion To Fuel For Earth And Mars, Anne J. Meier

USF Tampa Graduate Theses and Dissertations

As far as we know, we only have one planet to live on, with a delicate atmospheric system providing us safety and life. Global CO2 emissions continue to plague the environment of Earth, primarily due to the processing of fossil fuels, deforestation, and industrialization. There are several avenues of pursuing CO2 reutilization, each having their own benefits and limitations. Direct and indirect thermochemical approaches of CO2 conversion boast of efficient CO2 conversion rates but have limitations associated with the use of renewable hydrogen and high temperatures of operation. The work in this dissertation investigates low temperature photocatalytic CO2 conversion, a …

Defect Laden Metal Oxides And Oxynitrides For Sustainable Low Temperature Carbon Dioxide Conversion To Fuel Feedstocks, Debtanu Maiti

USF Tampa Graduate Theses and Dissertations

The current energy and environmental scenario in the world demands acute attention on sustainable repurposing of waste CO2 to high value hydrocarbons that not only addresses the CO2 mitigation problem, but also provides pathways for a closed loop synthetic carbon cycle. Difference in the scales of global CO2 emissions (about 40 Gtpa, 2017) and the carbon capture and sequestration (CCS) facilities (estimated cumulative 40 Mtpa, 2018) provokes active research on this topic. Solar thermochemical (STC) and visible light photocatalysis are two of the most promising routes that have garnered attention for this purpose. While STC has the advantages of high …

Sustainable Production Of Bio-Based Succinic Acid From Plant Biomass, Enlin Lo

USF Tampa Graduate Theses and Dissertations

Succinic acid is a compound used for manufacturing lacquers, resins, and other coating chemicals. It is also used in the food and beverage industry as a flavor additive. It is predominantly manufactured from petrochemicals, but it can also be produced more sustainably by fermentation of sugars from renewable feedstocks (biomass). Bio-based succinic acid has excellent potential for becoming a platform chemical (building block) for commodity and high-value chemicals.

In this study, we focused on the production of bio-based succinic acid from the fiber of sweet sorghum (SS), which has a high fermentable sugar content and can be cultivated in a …

Dynamic Modeling Of An Advanced Wastewater Treatment Plant, Komal Rathore

USF Tampa Graduate Theses and Dissertations

Advanced wastewater treatment plants have complex biological kinetics, time variant influent rates and long processing times. The modeling and operation control of wastewater treatment plant gets complicated due to these characteristics. However, a robust operational system for a wastewater treatment plant is necessary to increase the efficiency of the plant, reduce energy cost and achieve environmental discharge limits. These discharge limits are set by the National Pollutant Discharge Elimination System (NPDES) for municipal and industrial wastewater treatment plants to limit the amount of nutrients being discharged into the aquatic systems.

This document summarizes the research to develop a supervisory operational …

Promoter Effects On Iron-Based, Sba-15 Supported Ultra-High Temperature Fischer- Tropsch Catalysts, David P. Weber

USF Tampa Graduate Theses and Dissertations

Promoter effects on SBA-15 supported iron Fischer-Tropsch catalysts were investigated for their potential to improve high temperature catalyst performance. FTS catalysts promoted by manganese (0.15%-1.4%), copper (0.15%-1%), and potassium (0.5%-3%), with all percentages stated on the basis of mass percentage of final catalysts, were prepared and tested at 430°C and ambient pressure in a fixed bed reactor. Manganese showed the ability to promote the FT reaction, increasing both the CO conversion and the average chain length of hydrocarbon products. Compared to the unpromoted catalyst composed only of iron supported on SBA-15, 1.4%Mn (mass) promotion of 15% (mass) iron on SBA-15 …

Conversion Of Biomass To Liquid Hydrocarbon Fuels Via Anaerobic Digestion: A Feasibility Study, Ahmad Naqi

USF Tampa Graduate Theses and Dissertations

The use of biomass as a potential feedstock for the production of liquid hydrocarbon fuels has been under investigation in the last few decades. This paper discusses a preliminary design and a feasibility study of producing liquid hydrocarbon fuels from biomass through a combined biochemical and thermochemical route. The process involves anaerobic digestion (AD) of the biodegradable portion of the biomass to produce methane rich gas. The methane rich biogas stream is purified by removing contaminants and upgraded to liquid hydrocarbon fuel in a gas to liquid facility (GTL) via thermochemical conversion route. The biogas conversion involves two major steps: …

Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare

USF Tampa Graduate Theses and Dissertations

Perovskite-type oxides show irrefutable potential for feasible thermochemical solar-driven CO₂ conversion. These materials exhibit the exact characteristics required by the low temperature reverse water-gas shift chemical looping process. These properties include structural endurance and high oxygen redox capacity, which results in the formation of numerous oxygen vacancies, or active sites for CO₂ conversion. A major drawback is the decrease in oxygen self-diffusion with increasing perovskite particle size. In this study, the La_0.75Sr_0.25FeO₃ (LSF) perovskite oxide was combined with various supports including popular redox materials CeO₂ and ZrO₂ along with more abundant …