Chemical Engineering Commons^™

Global Sensitivity Analysis For A Comprehensive Char Conversion Model In Oxy-Fuel Conditions, Troy Michael Holland, Thomas H. Fletcher

Faculty Publications

Oxy-fired coal combustion is a promising potential carbon capture technology. Predictive CFD simulations are valuable tools in evaluating and deploying oxy-fuel and other carbon capture technologies either as retrofit technologies or for new construction. However, accurate predictive simulations require physically realistic submodels with low computational requirements. In particular, comprehensive char oxidation and gasification models have been developed that describe multiple reaction and diffusion processes. This work focuses on the sensitivity of a recent comprehensive char conversion code named CCK, which treats surface oxidation and gasification reactions as well as the processes such as film diffusion, pore diffusion, ash encapsulation, and …

Bioluminescent Magnetic Nanoparticles As Potential Imaging Agents For Mammalian Spermatozoa, Erick Salvador Vasquez, Jean M. Feugang, Scott T. Willard, Peter L. Ryan, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Background: Nanoparticles have emerged as key materials for developing applications in nanomedicine, nanobiotechnology, bioimaging and theranostics. Existing bioimaging technologies include bioluminescent resonance energy transfer-conjugated quantum dots (BRET-QDs). Despite the current use of BRET-QDs for bioimaging, there are strong concerns about QD nanocomposites containing cadmium which exhibits potential cellular toxicity.

Results: In this study, bioluminescent composites comprised of magnetic nanoparticles and firefly luciferase (Photinus pyralis) are examined as potential light-emitting agents for imaging, detection, and tracking mammalian spermatozoa. Characterization was carried out using infrared spectroscopy, TEM and cryo-TEM imaging, and ζ-potential measurements to demonstrate the successful preparation of these nanocomposites. Binding …

Carinata Fame Production Process And Biofuel Oxidation, Benoit Kindo

Honors College Theses

In this experiment, the contribution of a standard production method for biofuels on their oxidative stability was investigated. Peroxide values were measured at different steps of the production process of Brassica carinata and peanut-based biofuels. The washing and drying steps in this production method showed significant increases in peroxide values for both biofuels and was identified as a major contributor of biofuel oxidation. Further analyses of the physical and thermal properties showed a more pronounced affect in the biofuel from Bassica carinata, and indicated an unusual composition much higher in saturated fatty acids much longer than those found in peanut. …

Characterization Of Biochars Produced From Peanut Hulls And Pine Wood With Different Pyrolysis Conditions, James W. Lee, Bob Hawkins, Michelle K. Kidder, Barbara R. Evans, A. C. Buchanan, Danny Day

Chemistry & Biochemistry Faculty Publications

Background

Application of modern biomass pyrolysis methods for production of biofuels and biochar is potentially a significant approach to enable global carbon capture and sequestration. To realize this potential, it is essential to develop methods that produce biochar with the characteristics needed for effective soil amendment.

Methods

Biochar materials were produced from peanut hulls and pine wood with different pyrolysis conditions, then characterized by cation exchange (CEC) capacity assays, nitrogen adsorption–desorption isotherm measurements, micro/nanostructural imaging, infrared spectra and elemental analyses.

Results

Under a standard assay condition of pH 8.5, the CEC values of the peanut hull-derived biochar materials, ranging from …

Surface-Initiated Polymerizations For The Rapid Sorting Of Rare Cancer Cells, Jacob L. Lilly

Theses and Dissertations--Chemical and Materials Engineering

Cancer metastasis directly accounts for an estimated 90% of all cancer related deaths and is correlated with the presence of malignant cells in systemic circulation. This observed relationship has prompted efforts to develop a fluid biopsy, with the goal of detecting these rare cells in patient peripheral blood as surrogate markers for metastatic disease as a partial replacement or supplement to tissue biopsies. Numerous platforms have been designed, yet these have generally failed to support a reliable fluid biopsy due to poor performance parameters such as low throughput, low purity of enriched antigen positive cells, and insufficiently low detection thresholds …

Diffusion-Mediated Deposition Of Proteins, Ruiqian Zhan

Theses and Dissertations--Mechanical and Aerospace Engineering

Gradients of proteins play a prominent role in many biological processes, from development of multicellular organisms to chemical signaling in the immune system. Deposition of surface gradients is a way to permanently modifying a surface’s properties, resulting in the creation of novel materials which have widespread applications in biologically relevant fields, such as directed cell growth, production of biocompatible implantable materials, and creation of functional biosensors. These types of surfaces can also be used as an ex vivo tool to help understand many biological processes by mimicking the environment in gradient-related phenomena in a controllable way. However, despite the large …

An Overview Of Production And Development Of Ceramic Membranes, Shereen Kamel Amin, Heba Mohamed Abdallah, Mai H. Roushdy, Chakinaz Aly El-Sherbiny

Chemical Engineering

Ceramic membranes became one of the most important ceramic products because of their numerous benefits. Many attempts have been made by researchers to produce ceramic membranes with modified properties by varying their raw materials. Some of these attempts included incorporating wastes into their production process. Examples of such waste are fly ash wastes, glass waste, mud resulting from the hydro cyclone laundries, cortical bone animal, coal gangue, sawdust, construction waste and rice husk. An ideal waste would be priceless waste while at the same time assisting minimizing pollution. Such a situation deals with a dual economic and environmental aspect. This …

Reaction Parameters And Energy Optimisation For Biodiesel Production Using A Supercritical Process, Nessren Farrag, Mamdouh Gadalla, Mai Fouad

Chemical Engineering

No abstract provided.

Effect Of Ce And Co Addition To Fe/Al2o3 For Catalytic Methane Decomposition, Ahmed S. Al-Fatesh, Ashraf Amin, Ahmed A. Ibrahim, Wasim Ullah Khan, Moustafa A. Soliman, Raja L. Al-Otaibi, Anis H. Fakeeha

Chemical Engineering

Catalytic methane decomposition is studied in a fixed bed reactor. Two sets of bimetallic catalysts are employed, namely: 30%Fe-X%Ce/Al2O3 and 30%Fe-X%Co/Al2O3, and compared with monometallic 30%Fe/Al2O3 catalyst. The effect of promoting Fe with Ce and Co and reduction temperature are investigated. The results reveal that Ce addition has shown a negative impact on H2 yield while a positive effect on H2 yield and catalyst stability are observed with Co addition. In terms of number of moles of produced hydrogen per active sites, Fe/Al2O3 has shown a higher number of moles of hydrogen compared to bimetallic catalysts. The catalyst reduced at …

An Experimental Investigation Into The Effect Of Particulate Matter On Nox Reduction In A Scr Catalyst On A Dpf, Saksham Gupta

Dissertations, Master's Theses and Master's Reports

The study of NO_x reduction across the SCRF^® is presented in this report to understand the inlet and outlet NO, NO₂, NH₃ species from the SCRF^®. The SCRF^® is a prototype SCR catalyst on a Diesel Particulate Filter (DPF) that reduces NOx and PM at the downstream location. The SCRF^® reduces the packaging volume of the aftertreatment components in order to reduce the cost, volume and weight of the aftertreatment system. A total of 12 experiments were performed on a Cummins ISB 2013 280 hp engine and the aftertreatment system. The …

A Model Compound Study In Syngas Tar Reforming, Jaren Lee

LSU Master's Theses

Biomass or coal gasification are promising processes for renewable energy. However, a major operating problem in gasification is what to do with syngas byproducts such as H2S and tars (heavy hydrocarbons) that cause catalyst deactivation downstream. Studies have shown that rare earth oxides (REOs) doped with transition metals are promising catalysts for tar reforming in the presence of sulfur.(R. Li, Roy, Bridges, & Dooley, 2014) In Chapter 1, propane is studied as a model compound for tar reforming with transition metal-doped (e.g., Mn, Fe) REOs. These are compared to a typical commercial Ni/Al2O3 catalyst. The results showed that REO/TM catalysts …

A Numerical Investigation Of Wellbore Stability Problems Using An Elastoplastic Model, Chang Huang

LSU Master's Theses

Wellbore stability analysis acts an important role in the drilling design to avoid pipe-stuck, lost circulation and the other instability-induced problems. However, the conventional linear elastic model used by the industry is too conservative in predicting the mud weight window. This project is aimed at improving the accuracy of wellbore stability analysis. An elastoplastic model with Drucker-Prager yield criterion featured by strain hardening is proposed to characterize the rock behavior. Object-oriented finite element analysis simulator, NSMOOM, is programmed in MATLAB. The simulator is verified with the analytical solution in the elastic domain and with the commercial software ABAQUS in the …

Development Of Novel High-Throughput Methodologies To Evaluate The Thermal Stability Of High-Temperature Thin-Film Crystals For Energy Applications, Jonathan Kenneth Bunn

Theses and Dissertations

High temperature materials are used in a variety of energy applications such as jet turbines, high temperature sensors, and solid oxide fuel cells (SOFCs). Discovery of new materials and their optimization represents a difficult engineering challenge, as the materials have to be designed to have a high figure of merit during intense high temperature operations.

The large number of engineering considerations involved in the identification and optimization of such materials makes traditional one-by-one material investigations prohibitively time consuming. The time needed to explore large parameter domains can be significantly decreased through the use of high-throughput experimentation (HTE). HTE is an …

Investigation Of Heterogeneous Chemistry Of Pollutants In Flue Gas For Air And Oxy-Combustion, Benjamin D. Galloway

Theses and Dissertations

Due to increasing concerns associated with the emissions created from the combustion of coal, technologies are being modified or developed to limit many of these harmful emissions. The content of this thesis will focus on two technologies and the specific pollutants they seek to limit. The first investigated is selective catalytic reduction, which is utilized to decrease NO emissions. Due to the recent promulgation of the MATS regulations, focus has been on reducing the Hg emissions through the optimization of the SCR catalysts, making them bi-functional for NO reduction and Hg oxidation. The work presented here focuses on a novel …

Application Of The Finite Element Method To Solve Coupled Multiphysics Problems For Subsurface Energy Extraction, Milad Ahmadi

LSU Doctoral Dissertations

Fractures are a source of extra compliance in the rock mass. Fracture compliance can estimate the fracture roughness and the type of fluid filling the fracture. The focus of this research study in chapter 2 is to illustrate how the compliance ratio of rough fractures can diverge from the compliance ratio of smooth fractures. The imperfect interface of the fracture is modeled with saw-tooth-like structures. The defined saw-tooth-like structures of contact asperities impose an in-plane asymmetry in the shear direction. The compliance ratio of the rough fracture is larger than the compliance ratio of the smooth fracture. Interlocking and riding …

Simulation Studies For Relative Importance Of Unconventional Reservoir Subgrid Scale Physics Parameters, Yaakoub Youssef El Khamra

LSU Doctoral Dissertations

In this endeavor we attempt to better understand gas transport in shale gas reservoirs, specifically the impact and effects of different physical phenomena. We start by documenting the nature of the reservoirs and the need for accurate modeling of various physical phenomena in multiple interconnected continua. The physical phenomena of interest include non-linear Forchheimer flow, Knudsen diffusion in the form of slip "Klinkenberg" flow and adsorption/desorption. The numerical methods used in the reservoir simulator are also introduced, along with a derivation of the main equations used. Various verification and validation results are compared against manufactured and analytical solutions and finally …

Process Monitoring And Data Mining With Chemical Process Historical Databases, Michael Carl Thomas

LSU Doctoral Dissertations

Modern chemical plants have distributed control systems (DCS) that handle normal operations and quality control. However, the DCS cannot compensate for fault events such as fouling or equipment failures. When faults occur, human operators must rapidly assess the situation, determine causes, and take corrective action, a challenging task further complicated by the sheer number of sensors. This information overload as well as measurement noise can hide information critical to diagnosing and fixing faults. Process monitoring algorithms can highlight key trends in data and detect faults faster, reducing or even preventing the damage that faults can cause. This research improves tools …

Cobalt-Based Catalysts For The Conversion Of Biomass-Derived Syngas To Ethanol And Higher Oxygenates, Zi Wang

LSU Doctoral Dissertations

Higher oxygenates synthesis by catalytic conversion of synthesis gas are the potential approaches to replace fossil fuels and produce chemicals for pharmaceutical manufacture, detergents and polymer industry. Cobalt-based catalysts are the most promising catalysts to replace noble metal catalysts for producing ethanol, acetaldehyde and higher oxygenates via CO hydrogenation. The formation of higher oxygenates requires active sites that can adsorb CO non-dissociatively and insert to the alkyl intermediate. The hydrogenation of the CO-inserted intermediates yields C2 and C2+ oxygenates. The main focus of this study is to investigate the active site for non-dissociative CO adsorption, and the modification of the …

A Comparison Of Simple Global Kinetic Models For Coal Devolatilization With The Cpd Model, Andrew Richards, Thomas H. Fletcher

Faculty Publications

Simulations of coal combustors and gasifiers generally cannot incorporate the complexities of advanced pyrolysis models, and hence there is interest in evaluating simpler models over ranges of temperature and heating rate that are applicable to the furnace of interest. In this paper, six different simple model forms are compared to predictions made by the Chemical Percolation Devolatilization (CPD) model. The model forms included three modified one-step models, a simple two-step model, and two new modified two-step models. These simple model forms were compared over a wide range of heating rates (5000 to 10⁶ K/s) at final temperatures up to …

Variable Stress Orientations In The Offshore Nile Delta: The Role Of Salt As A Mechanical Detachment Horizon, Weicheng Zhang

Masters Theses

"The offshore Nile Delta is characterized by variations of the maximum horizontal stress orientation in subsalt and supra-salt sequences. Margin-parallel SH, typical for tertiary deltas, is observed for regions that are below or do not contain evaporites. In sequences underlain by evaporates pre-dominantly margin-normal SH is observed. This observation yielded the first conclusive in situ evidence that salt acts as a mechanical detachment layer. In this study, 3D finite element analysis (FEA) is used to simulate the total stress distribution in the offshore Nile Delta featuring evaporate sequences. Several parameters such as different salt sequence geometries, friction coefficient on faults, …