Engineering Commons^™

Cactus-Based Mucilage As A Natural Dispersant For Crude Oil Spills, Fei Guo

USF Tampa Graduate Theses and Dissertations

Oil spills are a critical threat to the marine environment, and the spilled oil as a source of pollution can have long-term adverse effects on the marine ecosystem. Traditional mechanical clean-up operations have apparent advantages for dealing with small and medium-scale oil spills. For large-scale oil spills, dispersants are a practical and minimally influential approach to the environment. As the dispersant components are iteratively updated, dispersants become more efficient and safer. However, the toxicity of the dispersants remains a significant impediment to their application. An efficient and non-toxic dispersant is increasingly becoming a requirement.

The cactus mucilage extracts studied in …

Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar

USF Tampa Graduate Theses and Dissertations

Geological carbon sequestration in a saline formation is a promising technology for large-scale carbon dioxide (CO2) mitigation. Several factors such as temperature, pressure, salinity, hydraulic conductivity, and mineralogy of a formation affect the CO2 sequestration in saline formations. These factors can vary widely depending upon the type of formation or the degree of heterogeneity within a formation. In addition to these properties of the repositories, the CO2-rich flue gas streams captured from point sources often contains small amounts of impurities such as sulfur oxides (SOx) and nitrogen oxides (NOx), which may have serious implications on the chemistry of the repositories …

Responsive Coatings And Functional Systems From Pectin Polysaccharides, Zeinab Veisi

USF Tampa Graduate Theses and Dissertations

Pectin polysaccharides provide promising potential as all-natural, non-toxic “green” coatings. Pectin polysaccharides have been drawing growing attention as elements of stimuli-responsive systems and as source materials for functionalized robust coatings. They can be extracted from several natural sources and are intrinsically biocompatible. The majority of the applications of pectin gels require a better understanding of the properties of thin layers of gels at surfaces and interfaces. Despite the prevalence of bulk gels of pectin, coatings of pectin have not been reported. In bulk hydrogels, swelling of polymer networks is controlled by a diffusion limited transport process in which the rate …

Carbon Dioxide Adsorption Using Solid Amine Sorbents, Umadevi Gopalakrishnan

USF Tampa Graduate Theses and Dissertations

Biogas, being rich in methane, can be used as a fuel for various end uses such as electricity generation, compressed natural gas (CNG), production of liquid fuels, industrial heating, etc. CO₂ is the major contaminant in biogas (30–50%) along with other impurities such as NH₃, H₂S, and water. CO₂ in the biogas decreases the heating value of biogas. Natural gas pipelines and vehicle use require high purity (> 95%) CH₄. There are many commercial techniques available for CO₂ removal from biogas such as such water scrubbing (WS), chemical scrubbing (CS) using …

Effect Of Promoter (Mn) On The Performance Of Sba-15 Supported Iron Catalysts For High Temperature Fischer-Tropsch Synthesis, Sreya Mariya Seby

USF Tampa Graduate Theses and Dissertations

Development of an effective High Temperature Fischer-Tropsch Synthesis (HTFTS) catalyst is of interest in process intensification that combines methane reforming with long chain hydrocarbon production. Literature indicates iron catalysts supported on mesoporous silica performed relatively well in high temperature applications. In this work, we investigated the effect of manganese promoter on iron catalysts for FTS at 430 °C as it was known from previous studies that manganese promotion could enhance the CO conversion with higher hydrocarbon yields. Also, the effect of temperature on FTS activity was evaluated by testing the base and promoted Fe/SBA-15 catalysts for temperature ranging from 370 …

Sorption Of Benzene, Tolueneand Ethylbenzeneby Plasticized Pema And Pema/Pmma Sensing Films Using Aquartz Crystal Microbalance (Qcm) At 298.15k, Deekshitha Adapa

USF Tampa Graduate Theses and Dissertations

Detection of volatile organic compounds (VOC’s) in the environment is important for human health and wellness. Long term exposure of certain VOC’s like benzene, toluene, ethylbenzene and xylene (BTEX) has a severe effect on human health. There are techniques such as gas chromatography, photo ionization, and mass spectroscopy that are time consuming, require gas sampling and are ineffective in real time sensing in air. Acoustic wave devices such as surface acoustic wave (SAW) devices can be used for sensing BTEX compounds in both vapor and liquid phase. The quartz crystal microbalance (QCM) is a low-frequency acoustic wave device, which can …