Chemical Engineering Commons^™

Volume-Phase Transitions In Responsive Photo-Cross-Linked Polymer Network Films, Leena Patra

USF Tampa Graduate Theses and Dissertations

The overall thrust of this project is to gain an insight into a class of surface-tethered cross-linked thin films of poly(N-alkylacrylamides) that display a lower critical solution temperature (LCST).The structure of the alkyl group and the modification of the amide groups determine the LCST and resultant volume-phase transition behavior. The aim of this study involves synthesis and characterization of thin films and to correlate the volume-transition behavior to the structure of the alkyl group. For better understanding the volume-transition behavior, the polymer films are perturbed by the Hofmeister salt series to examine trends between different alkyl groups. While most of …

Modeling Carbon Sequestration In Transition Zone To Optimize Storage Potential, Fang Yang

Doctoral Dissertations

"Shallow aquifers are potential candidates for carbon sequestration because of their wide distribution and low injection cost. Injected CO₂ in a shallow region segregates into two zones according to CO₂ phases within the initial reservoir pressure and the maximum bottom hole pressure: gas zone and transition zone. Transition zone is a better option because of favorable CO₂ properties. This work investigated the CO₂ storage potential in transition zone using the compositional simulator CMG-GEM and a design of experiment software iSIGHT. First, it addressed the basic characteristics of CO₂ sequestration in transition zone, and then modeled CO₂ injection with simultaneous water …

Novel Blends Of Sulfur-Tolerant Water-Gas Shift Catalysts For Biofuel Applications, Timothy Michael Roberge

USF Tampa Graduate Theses and Dissertations

As traditional sources of energy become depleted, significant research interest has gone into conversion of biomass into renewable fuels. Biomass-derived synthesis gas typically contains concentrations of approximately 30 to 600 ppm H2S in stream. H2S is a catalyst poison which adversely affects downstream processing of hydrogen for gas to liquid plants. The water-gas shift reaction is an integral part of converting CO and steam to H2 and CO2. Currently, all known water-gas shift catalysts deactivate in sulfur concentrations typical of biomass-derived synthesis gas. Novel catalysts are needed to remain active in the presence of sulfur concentrations in order to boost …

Catalytic Tri-Reforming Of Biomass-Derived Syngas To Produce Desired H2:Co Ratios For Fuel Applications, Devin Mason Walker

USF Tampa Graduate Theses and Dissertations

This study focuses on upgrading biomass derived syngas for the synthesis of liquid fuels using Fischer-Tropsch synthesis (FTS). The process includes novel gasification of biomass via a tri-reforming process which involves a synergetic combination of CO2 reforming, steam reforming, and partial oxidation of methane. Typical biomass-derived syngas H2:CO is 1:1 and contains tars that deactivate FT catalyst. This innovation allows for cost-effective one-step production of syngas in the required H2:CO of 2:1 with reduction of tars for use in the FTS. To maximize the performance of the tri-reforming catalyst, an attempt to control oxygen mobility, thermal stability, dispersion of metal, …

Smart Packaging: A Novel Technique For Localized Drug Delivery For Ovarian Cancer, Eva Christabel Williams

USF Tampa Graduate Theses and Dissertations

Localized drug delivery is emerging as an effective technique due to its ability to administer therapeutic concentrations and controlled release of drugs to cancer sites in the body. It also prevents the contact of harsh chemotherapy drugs to healthy regions in the body that otherwise would become exposed to current treatments.

This study reports on a model chemotherapy drug delivery system comprising non-ionic surfactant vesicles (niosomes) packaged within a temperature-sensitive chitosan network. This smart packaging, or package-within-a package system, provides two distinct advantages. First, the gel prevents circulation of the niosomes and maintains delivery in the vicinity of a tumor. …

Shape-Shifting Surfaces For Rapid Release And Direct Stamping Of Organized Micro-Tissues, Samuel James Dupont

USF Tampa Graduate Theses and Dissertations

The primary aim of the research in this study is to develop a robust and simple platform for the in vitro organization of cells on surfaces which facilitate rapid cell release and allows for the direct stamping of highly organized micro-tissues. Current approaches towards this goal have been very successful but are lengthy and subject cells to harsh conditions for extended periods of time raising questions regarding cell health and maintenance of physiological state. To address these concerns a platform was developed to allow for rapid cell release by utilizing a release mechanism different from previous work.

Micron-scale structures comprised …

Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin

USF Tampa Graduate Theses and Dissertations

Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue.

Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per …