Chemical Engineering Commons^™

Polymeric Nanoparticle As A New Platform For High Removal Of Endotoxins From Biopharmaceutical Solutions, Sidharth Razdan

Doctoral Dissertations

"Presently, approximately one-third of all biopharmaceutical drugs are derived from biological sources like gram-negative bacteria. Gram-negative bacteria like E.coli are much cheaper to cultivate and provide higher biotherapeutic yield compared to mammalian cells. On extracting the useful biotherapeutics from the gram-negative bacterial cells (E.coli), endotoxin present in the bacteria is released in the surrounding media thus contaminating the lifesaving biotherapeutics. Application of the endotoxin-contaminated therapeutics to humans or animals can cause serious health issues like septic shock, tissue injury and ultimately death. Hence, thorough purification of biotherapeutics before parenteral application is necessary. Although there are multiple methods for …

Strategies To Improve The Electrochemical Performance Of Lithium-Ion Batteries By Stabilizing The Interface Of Electrode/Electrolyte, Ye Jin

Doctoral Dissertations

”Lithium-ion batteries (LIBs) provide great potential for electric vehicles, and smart grids as future energy-storage devices. However, there are many challenges in the development of the LIB industry, including low energy and power density of electrode materials, poor rate performance, short cycle life of electrode materials, and safety issues caused by the flammability of the conventional organic liquid electrolytes.

In this research, we were committed to using general approach to efficiently and economically synthesize or modify LIB materials by stabilizing the interface between electrode and electrolyte. Atomic layer deposition (ALD) method was used to coat metal oxide thin films on …

Mechanisms Of Pathogen Inactivation In Wastewater And Pharmaceutical Applications, Christa L. Meingast

Dissertations, Master's Theses and Master's Reports

Infectious diseases are a significant threat to public health. Though society enacts practices to prevent the spread of these dangerous diseases, challenges remain. Therefore, continual advancements in treatment and prevention are required. Wastewater treatment and viral clearance in pharmaceutical applications are two key health measures that prevent the spread of infections.

A low-cost, low-technology biosolids treatment process was developed to improve wastewater treatment by collecting key information on storage temperature, ammonia, volatile solids, moisture content, pH, and pathogen inactivation in biosolids over long-term storage at two wastewater treatment plants located in northern climates of the United States. Inactivation of pathogens …

Virus Purification Framework And Enhancement In Aqueous Two-Phase System, Pratik Umesh Joshi

Dissertations, Master's Theses and Master's Reports

Viral infections regularly pose detrimental health risks to humans. Preventing viral infections through global immunization requires the production of large doses of vaccines. The increasing demand for vaccines, especially during pandemics such as COVID-19, has challenged current manufacturing strategy to develop advanced unit operations with high throughput capability. Over the decade, the upstream processing responsible for synthesizing viral products in cell cultures has shown significant success in yielding high titers of viruses and virus-like particles. The progress in the upstream stage has now shifted the bottleneck to the downstream processing (DSP). Overlooked for decades, the DSP responsible for viral product …

Role Of Flocculation And Dispersion In Pelletization Of Iron Ore, Victor J. Claremboux

Dissertations, Master's Theses and Master's Reports

Traditional modeling of iron ore pellet strength utilizes micromechanical models such as Rumpf’s equation, which correlate attractive forces and pellet properties into an average expected pellet strength. These models combine with repulsive forces within pellets to predict that pellet strength decreases with the introduction of these forces. However, naïvely applying Rumpf’s equation readily leads to incorrect predictions about the resulting behavior. Pellets created with strong repulsive forces arising from dispersion conditions are observed to be significantly stronger overall than pellets formed in the absence of dispersants. A new model is required to understand and predict the effects of these additives …

Electrification Of Domestic Hot Water To Aid The Integration Of Renewable Energy In The California Grid, Alejandro Cervantes

Cal Poly Humboldt theses and projects

Water heating in residential buildings, also known as domestic hot water (DHW), is the third largest use of energy after appliances and space conditioning. About 90% of the residential buildings in the state use natural gas fueled water heaters, 6% use electricity, and a small percent use liquefied petroleum gas (LPG) or solar water heaters. The current energy use associated with residential water heating is small relative to the total amount of energy consumption in the residential building sector, but it is still a contributor of greenhouse gas (GHG) emissions. Improving hot water systems can be beneficial for bill customer …

Towards Efficient Water Treatment: Mechanism Of Colloidal Fouling Of Ultrafiltration Membranes, Ikenna Henry Ozofor

Dissertations, Master's Theses and Master's Reports

This research study first reviewed challenges of conventional and membrane separation systems for water treatment. Though membrane separation systems appeared superior to the conventional counterparts for water and wastewater treatment, wider applications of membrane systems have been limited by some factors, most notably is membrane fouling. Experimental studies were therefore conducted to achieve the goal of this research, which is to investigate how feed properties affect fouling of ultrafiltration (UF) membranes by colloids.

Feed salinity, pH, and nanoparticle concentration were the variables studied to unravel how different UF membranes are fouled by model silica colloids (with average diameter of 25nm). …

Continuous Viral Vaccine Manufacturing And Viral Detection Strategies, Dylan G. Turpeinen

Dissertations, Master's Theses and Master's Reports

Viruses are responsible for many human diseases that lead to suffering and death. Acquired immunodeficiency syndrome (AIDS), influenza, and coronavirus disease 2019 (COVID-19) have claimed the lives of millions of people. Two methods have been created to reduce the suffering caused by these diseases. The first is the manufacturing of vaccines that prevent disease and the second is the development of virus detection tests that lead to treatment. The work summarized in this dissertation discusses the development of a continuous virus purification process using an aqueous two-phase system for use in vaccine manufacturing. Additionally, two novel virus detection methods were …

Fabrication, Characterization And Applications Of Highly Conductive Wet-Spun Pedot:Pss Fibers, Ruben Sarabia Riquelme

Theses and Dissertations--Chemical and Materials Engineering

Smart electronic textiles cross conventional uses to include functionalities such as light emission, health monitoring, climate control, sensing, storage and conversion of energy, etc. New fibers and yarns that are electrically conductive and mechanically robust are needed as fundamental building blocks for these next generation textiles.

Conjugated polymers are promising candidates in the field of electronic textiles because they are made of earth-abundant, inexpensive elements, have good mechanical properties and flexibility, and can be processed using low-cost large-scale solution processing methods. Currently, the main method to fabricate electrically conductive fibers or yarns from conjugated polymers is the deposition of the …

Nanostructured Metal Thin Films As Components Of Composite Membranes For Separations And Catalysis, Michael J. Detisch

Theses and Dissertations--Chemical and Materials Engineering

Novel metallic thin film composite membranes are synthesized and evaluated in this work for improved separations and catalysis capabilities. Advances in technology that allow for improved membrane performance in solvent separations are desirable for low molecular weight organic separation applications such as those in pharmaceutical industries. Additionally, the introduction of catalytic materials into membrane systems allow for optimization of complex processes in a single step. By adding a nanostructured metallic thin film to its surface, a polymer membrane may be modified to exhibit these improved properties. Using magnetron sputtering, thin metal films may be deposited on commercially available membranes to …

A Thermodynamic And Feasibility Study Of Green Solvents For The Fabrication Of Water Treatment Membranes, Xiaobo Dong

Theses and Dissertations--Chemical and Materials Engineering

Nonsolvent induced phase separation (NIPS) has been widely used to fabricate polymeric membranes. In NIPS, a polymer is dissolved in a solvent to form a dope solution, which is then cast on a substrate and immersed in a nonsolvent bath, where phase inversion occurs. Petroleum-derived organic solvents, such as N-Methyl-2-Pyrrolidone (NMP) and Dimethylacetamide (DMAc), have been traditionally used to fabricate polymeric membranes via NIPS. However, these solvents may have negative impacts on environmental and human health; therefore, using greener and less toxic solvents, preferably derived from biomass, is of great interest to make membrane fabrication sustainable. In this dissertation, two …

Homotopy Simulation Of Dissipative Micropolar Flow And Heat Transfer From A Two-Dimensional Body With Heat Sink Effect: Applications In Polymer Coating, O. A. Bég, B. Vasu, A. K. Ray, T. A. Beg, A. Kadir, H. J. Leonard, Rama S. R. Gorla

Faculty Publications

Non-Newtonian flow from a wedge constitutes a fundamental problem in chemical engineering systems and is relevant to processing of polymers, coating systems, etc. Motivated by such applications, the homotopy analysis method (HAM) was employed to obtain semi-analytical solutions for thermal convection boundary layer flow of incompressible micropolar fluid from a two-dimensional body (wedge). Viscous dissipation and heat sink effects were included. The non-dimensional boundary value problem emerges as a system of nonlinear coupled ordinary differential equations, by virtue of suitable coordinate transformations. The so-called Falkner-Skan flow cases are elaborated. Validation of the HAM solutions was achieved with earlier simpler models, …

Time-Dependent Reliability Framework For Durability Design Of Frp Composites, Rajneesh Kumar Bharil

Graduate Theses, Dissertations, and Problem Reports

The life-cycle performance, durability, and aging characteristics of Fiber Reinforced Polymer (FRP or Structural Composites) have been of keen interest to the engineers engaged in the FRP design, construction, and manufacturing. Unlike conventional construction materials such as steel and concrete, the design guidelines to account for the aging of FRP are somewhat scattered or not available in an approved or consistent format. Loss of strength over time or aging of any structural material should be of concern to engineers as the in-service lifespan of many engineering structures is expected to exceed 100 years. Use of durability strength-reduction factors or factors …

Process Modeling And Techno-Economic Analysis Of Thermo-Catalytic Dimethyl Ether Synthesis And Microwave-Based Aromatics Production Technologies From Shale Gas, Chirag Mevawala

Graduate Theses, Dissertations, and Problem Reports

Production of dimethyl ether (DME) and direct non-oxidative methane dehydroaromatization (DHA) to aromatics via conventional and microwave (MW)-assisted processes are investigated in this research. Plant-wide models of the shale gas to DME process with integrated CO₂ capture via direct and indirect synthesis routes have been developed. Optimal parameter estimation, and model validation are undertaken for various sections of the process including the pre-reforming reactor, auto-thermal reforming reactor, DME synthesis reactors, CO₂ capture units and separation sections. A novel DME separation process has been developed for efficient separation of DME, syngas, and CO₂. Plant-wide techno-economic optimization is …

Next Generation Of Applications Of Metal-Organic Frameworks For Energy And Environmental Sustainability, Qian Liu

Graduate Theses, Dissertations, and Problem Reports

My PhD work aimed at using Metal-organic frameworks (MOFs) for mitigating the environmental issues and energy crisis associated with anthropogenic activities. Specifically, we developed robust platforms and/ or systems using MOF as “scaffolds” to allow for model pollutant detection and CO₂ sequestration and benign transformation respectively.

First, I detailed how photocatalytic properties of 2,5-furandicarbocylic acid (FDCA) in its alone and its MOF- integrated form (MIL-160) were used for the first time for the reduction of Ag⁺ at room conditions. Such photocatalytic activities could then be used in user-designed hybrids (i.e., Ag/MIL-160) to form sensorial platforms for prevalent phenol …

Dynamic Study Of Mo/Zsm-5 Catalyst For Ch4 Dehydroadomation, Hadi Yahya Almusawa

Graduate Theses, Dissertations, and Problem Reports

Methane dehydroaromatization (CH₄-MDA) is a highly promising venture for natural gas utilization/exploitation, i.e., direct conversion of methane (CH₄) to liquid aromatics (benzene) and hydrogen. This process is a catalytic reaction and therefore, is subject to all the advantages and constraints of catalysis. This study discussed the structure and reactivity of Mo/ZSM-5 zeolite catalysts and their effect on the active conversion of methane to valuable aromatic products such as benzene: 1) The preparation and characterization of Mo/ZSM-5, which are crucial steps in any catalytic reaction process since a better performing catalyst consequently leads to better outcomes; 2) …

Elucidating The Properties And Mechanism For Cellulose Dissolution In Tetrabutylphosphonium-Based Ionic Liquids Using High Concentrations Of Water, Brad Crawford

Graduate Theses, Dissertations, and Problem Reports

The structural, transport, and thermodynamic properties related to cellulose dissolution by tetrabutylphosphonium chloride (TBPCl) and tetrabutylphosphonium hydroxide (TBPH)-water mixtures have been calculated via molecular dynamics simulations. For both ionic liquid (IL)-water solutions, water veins begin to form between the TBPs interlocking arms at 80 mol % water, opening a pathway for the diffusion of the anions, cations, and water. The water veins allow for a diffusion regime shift in the concentration region from 80 to 92.5 mol % water, providing a higher probability of solvent interaction with the dissolving cellulose strand. The hydrogen bonding was compared between small and large …

Customized Boron And Magnesium-Based Reactive Materials Prepared By High Energy Mechanical Milling, Xinhang Liu

Dissertations

New reactive materials need to be developed having biocidal combustion products. When ignited, such material can add chemical biocidal effects to the common effects of high temperature and pressure. Biocidal combustion products are capable of deactivating harmful spores or bacteria, which can be released by targets containing biological weapons of mass destruction. Research showed that halogens, especially iodine, are effective as biocidal components of reactive material formulations. Recently, magnesium combustion product MgO is also found to have a biocidal effect. Thus, advanced formulations containing both magnesium and iodine are of interest; such formulations are prepared and investigated here.

Reactive materials …

Indonesia Natural Mineral For Heavy Metal Adsorption: A Review, Grandprix T. M. Kadja, Moh Mualliful Ilmi

Journal of Environmental Science and Sustainable Development

Indonesia has abundant mineral resources used as natural adsorbent materials for the absorption of heavy metal. Among these are natural zeolites, clay, and ashes. These natural materials showed high performance adsorption capacity with respects to their low cost and high availability. Several research reports had been published for studying the performance of the natural materials as adsorbent of several heavy metals i.e., Hg, Pb, Fe, Cd, Cr, Zn, Ni, and Cu by examining the effect of various factors, including pH, contact time, initial concentration, temperature, and dosage. Furthermore, to determine the adsorption rate, mechanism, and efficiency of natural materials in …

A New Interpretation Of The √7×√7 R19.1° Structure For P Adsorbed On A Ni(111) Surface, Elizabeth Barrow, Grant S. Seuser, Hiroko Ariga-Miwa, Donna A. Chen, Jochen A. Lauterbach, Kiyotaka Asakura

Faculty Publications

We have studied P adsorption on Ni(111), a system which shows complex adsorbate structures. We determined the phase diagram of the surface P adsorbed on Ni(111). At low coverage, amorphous P was observed. At temperatures between 373 and 673 K and coverages above 0.1 monolayer, we found a √7×√7 R19.1° structure, but above 673 K, other complex structures were created. These structures seemed to correlate with each other and we reinterpret a √7×√7 R19.1° structure of P adsorbed on Ni(111) based on the similarities of these surface structures. The new rectangular structure for the √7×√7 19.1° is discussed in relation …