Chemical Engineering Commons^™

Investigating The Rheological Behavior Of A Simple Yield Stress Fluid Under Shear Flows, Francesco Accetta

Theses

Many soft materials display unique and complex rheological behavior characterized by a transition from a solid-like to a fluid-like state upon the application of a force that exceeds the threshold to flow, known as the yield stress. Yield stress fluids are found in a wide range of commonly encountered materials including microgels, emulsions, and foams, and have been widely studied by rheologists over the last several decades. Carbopol is a popular polymeric microgel system as it displays simple, non-thixotropic rheological behavior and is typically seen as an ideal yield stress fluid. Previous research has demonstrated the reproducible behavior of shear …

Novel Investigation Of Catalytic Hydrogenation And Oxidation Of 1,3-Butadiene, Ali M. Alabedkhalil

Theses

The hydrogenation of 1,3 Butadiene (BD) is an important industrial process that is generally used to generate butene, which is a key feedstock to produce a variety of chemicals such as polymers, plastic, and synthetic rubber. This process involves reacting BD with hydrogen using different metallic Ni-based catalysts. In this study, Ni/Al₂O₃ and Ni/Nb₂O5 catalysts were used and investigated to perform the hydrogenation reaction because of their commercial availability, effective hydrogenation activity, and affordability compared to Platinum Group Metal (PGM) catalysts.

The catalytic reactions were conducted using a quartz tube reactor between a temperature range …

Utilizing Date Pits In Microencapsulation: Effect Of Different Variations On Probiotic Survivability Under In Vitro Digestion, Asmaa Samir Al Hamayda

Theses

This work deals with the medicinal use of date pit powder, which turns it from a waste product to a useful stabilizer for the release of beneficial probiotics in the human intestine. The main objective of this work is to encapsulate probiotics with date pit beads and their subsequent release in the human intestine. The beads were formed using gravitational dripping technique, while INFOGEST protocol was used to test the digested beads and the release of viable probiotic cells. For the three date varieties Raziz, Naghal and Khadrawy, it was found that 0.1 g of date pit powder per 0.2 …

Effects Of Wettability, Lithology, And Permeability On The Optimum Slug Size Of Low Salinity Water Flooding In Carbonates: An Experimental Approach, Hala Khaled Hasan Alshadafan

Theses

Low salinity water flooding has attracted academic and industry communities due to its relatively simple and applicable technology. One of the drawbacks of applying the IOR/EOR technique is the lack of the availability of low salinity water in large quantities at the reasonable cost required for a technically and environmentally successful project. To overcome this problem, the industry proposed to use produced water/sea water after dilution, and reverse osmosis filter technology to achieve the required salinity. Both techniques are quite costly and might hinder the project's economic success. Low salinity water as slug size followed by high salinity water was …

A Detailed Parameter Study Into The Dermal Absorption Of Chemical Warfare Agents And The Effects Of Pharmacokinetics, Koko Lear

Theses

Chemical warfare agents (CWAs) are substances of varying toxicity profiles. These chemicals exhibit complex dynamics and pose a serious health risk when released into the environment. A mathematical model based on Fick’s second law of diffusion was developed to comprehend how these compounds were absorbed into the skin. The analysis applied to both small and large doses and, successfully, predicted experimental results. This work also includes the effects of CWA physicochemical properties on evaporation and dermal absorption through the stratum corneum. A sensitivity analysis was conducted to assess the impacts of small variations in the initial dose, environmental conditions, and …

Desalination Waste Revitalization Using Carbon Capture: Process Optimization Using Machine Learning, Ahmed Mohamed Elsayed

Theses

Over the next five to ten years, desalination will play an ever-important role in our society. Developing nations will look at desalination from the point of water scarcity, while developed nations will consider the perspective of the Water-Energy-Food nexus. With current technology, for every liter of freshwater produced, one and a half liters is thrown away as waste. This body of research proposes to employ chemical precipitation in ammoniated brine solutions, that have reasonably high ionic concentrations. CO2 absorption in Bubble Column Reactors can reduce sodium ions by precipitating NaHCO3. Also, the absorbed CO2 can reduce chloride ions and induce …

Possible Storage Of Co₂ In Saline Aquifer: Storage Factor Estimation, Sarah Abdul Aziz Al-Tamimi

Theses

The objective of this study is to perform laboratory measurements and a CO₂ underground storage study to cover the knowledge gap on CO₂-Brine relative permeability and assess various variables on the storage of CO₂ in a selected aquifer. Several factors that affect CO₂ storage have been discussed in the literature. These include both macroscopic and microscopic displacement efficiency of brine as a function of CO₂ pore volume injected. It is clear from the literature that there is still more work needed to investigate the effect of various variables such as formation temperature, brine viscosity, and the possible presence of free …

Flexible Microfluidic Device With Nonplanar Interdigitated Microelectrodes, Saud Alssaidy

Theses

The lab-on-a-chip concept has improved significantly in recent years to meet global demand for various applications with the advent of new technologies. Much progress has been achieved, but many microfluidic devices still suffer from design limitations in terms of sensitivity and selectivity because they use rigid, fragile substrate materials and conventional electrodes, which do not provide high sensitivity or selectivity and suffer from signal-to-noise ratio issues. This work proposes a novel device architecture that uses flexible, transparent top and bottom layers integrated with (nonplanar interdigitated microelectrodes) to create a sandwich-like flexible substrate base. The top and bottom layers consist of …

Itraconazole Nanocomposites Prepared Via Rotary Evaporator Drying Of Nanomilled Suspensions, Alexander Santos Coelho

Theses

The aim of this study is to explore the feasibility of rotary evaporation for drying wetmilled drug suspensions as a novel approach to produce drug nanocomposites that exhibit fast redispersion and immediate drug release. To this end, the physical stability of the nanomilled itraconazole (drug) suspensions, a.k.a., nanosuspensions, during the milling and storage; the drying of the itraconazole nanosuspensions via the rotary evaporator; and the type/loading of various polymers/surfactants (dispersants) on aqueous redispersion and drug release from the nanocomposites were examined. Our results suggest that smaller drug particle size, owing to nanomilling, and smaller nanocomposite particle size, owing to optimized …

Immobilized Lipase On Zif For Enhanced Biofuel Production, Reem Mohammed Al Mansouri

Theses

Enzymatic transesterification of triglycerides to produce biodiesel has been gaining increasing attention owing to its advantages over chemical processes. Being catalysts, enzymes are not consumed during the processes in which they are used. Therefore, a successful technique to allow their repeated use can significantly enhance the economic feasibility of the process. The most common approach to allow easy separation of the enzymes and to eliminate their wastage is immobilization on a support matrix. Recently, Metal-Organic Frameworks (MOFs) have been suggested as preferable support for enzyme immobilization, owing to their high-order structure and high porosity and specific surface area. This thesis …

Immobilization Of Lipase On Metal Organic Frameworks For Biodiesel Production, Reem L Safwan Shoma

Theses

For the economical application of enzymatic processes in biodiesel production, lipase enzyme has to be used in immobilized form to allow easy retention and reuse. The main challenges facing the industrialization of the enzymatic process are the high mass transfer resistance, the tendency to adsorb the by-product glycerol onto the support matrix and poor operational stability. These problems can be solved by a good selection of supports of favourable surface characteristics and pore sizes. In that regard, increasing interest has recently been in Metal-Organic Frameworks (MOFs) as a new kind of porous support for enzyme immobilization. Physical adsorption, which is …

Extraction And Bioactivity Evaluation Of Antioxidant Components From Teucrium Stocksianum Bioss Collected From Uae, Ahmad Ayman Al Salloum

Theses

Recently, the industry of Natural Bioactive Compounds (NBAC) is expanding dramatically due to its high medical potentials. High bioactivity of natural extracts from a wide range of plants is evident from the reported literature. For instance, NBACs show antibacterial, antifungal, antimicrobial, anti-inflammatory, anticancer and antioxidant activities. Teucrium stocksianum Boiss. from the Lamiaceae family is a known herb in the traditional medicine in United Arab Emirates. Multiple bioactivities of T. stocksianum were recorded such as anti-inflammation, analgesia, antioxidation, anticancer, antinociception and antimicrobial bioactivity. In this thesis, the extraction of NBACs from T. stocksianum was studied with Microwave-assisted extraction using Deep eutectic …

Study Of Electrodeposition Of Copper-Indium Material For Fabrication Of Cis Thin-Film Solar Cells, Leher Farooq

Theses

Abstract

Copper-Indium material for the fabrication of CIS/CIGS thin-film solar cells and for applications as an alloy is one of the most auspicious materials currently being studied and has attracted significant interest in solar energy and other industries. In the past, there have been several methods used for the fabrication of chalcopyrite thin-film solar cells. However, one of the best methods in the industry is electrodeposition, which employs the principles of electrochemistry to deposit materials on a working electrode. The cyclic voltammetry and constant potential deposition studies have been conducted for the electrodeposited copper indium material. In order to better …

Electrodeposition Study Of Alloys For Solar Energy, Corrosion Resistance, And Battery Applications, Thaier Tawfeek Alawadh

Theses

Copper-Zinc-Tin sulphide (CZTS) compound is one of the alloys, which has significantly caught the attention of a considerable number of researchers since the beginning of the century. Consequently, academic laboratories started investigating the alloy in-depth with its various combination due to its valuable applications with high potential usage. The CZTS alloy has a high tendency to replace the current copper indium gallium selenide (CIGS) thin-film solar cell system due to scarcity of CIGS components, and toxic manufacturing procedures compared to CZTS. Nevertheless, CZTS is a new studied compound with exceptionally low photovoltaic empirical efficiency and an inadequate understanding of its …

Preparation And Characterization Of Reactive Composites Combining Boron With Mixed Oxides, Purvam Mehulkumar Gandhi

Theses

Thirteen liquids have been explored as Process Control Agents (PCAs) for high-energy mechanical milling of two metal oxide powders, CuO and Bi₂O₃, with the practical purpose to reduce the sizes of powder particles and refine their crystal structure. Multiple liquid properties have been considered to analyze their effect on evolution of both particle and crystallite sizes during milling for each oxide. Experimental data were analyzed using the δ-AICc (Akaike Information criterion) correlation function applied to linear relations between liquid properties and powder characteristics. Multiple linear correlation models were ranked based on the highest log-likelihood and the …

Calcium Phosphate/Ionic Liquid Ptfe Composite Membrane For Proton Exchange Membrane Fuel Cell Applications, Ahmad Ibrahim Hasan Ka’Ki

Theses

The dependence on fossil fuels can be possibly reduced by the utilization of renewable energy sources. Fuel cells offer a promising alternative for renewable power generation. Among the various types of fuel cells, Proton Exchange Membrane Fuel Cell (PEMFC) is recently attracting attention due to its several advantages of high-power density, all solid structure, and silent operation. The diverse types of materials used in this type of fuel cell raised drawbacks related to fuel cell cost and durability. By far, Nafion of DuPont is still the current state-of-the-art membrane for PEMFCs. It is known for its high ionic conductivity and …

Developing A New Formula For Predicting Oil Recovery Factor In Water Flooded-Heterogeneous Reservoirs, Mohamed Khaled Aljifri

Theses

In this work, two sets of empirical correlations were developed for predicting the recovery factor (RF) in water-flooded layered oil reservoirs. The first set of these correlations encompasses four key parameters believed to have a significant impact on waterflooding performance, namely, reservoir heterogeneity (permeability variation coefficient), injected water viscosity, permeability anisotropy (ratio of vertical permeability to horizontal permeability), and water injection rate. This first set consists of two expanded forms, one for predicting the RF at water breakthrough time (BT) and the other for predicting the RF at the end of the project (EOP). Out of the aforementioned four key …

Poly (Lactic Acid)/Nanoclay Nanocomposites For Packaging Applications, Maissa Akram Adi

Theses

With increasing stringent environmental regulations and attempts to reduce dependence on fossil fuels for polymer production, bio-based polymers are receiving appreciable global attention. In this context, bio-based poly (lactic acid) (PLA) is one of the most frequently used polymers in packaging applications. However, despite of its high versatility, this polymer is limited in packaging applications due to its low mechanical properties. The two-dimensional nanofillers such as nanoclay and graphene are well known for improving the thermo-mechanical properties of polymers at low concentrations. However, increasing higher filler concentration to improve barrier properties of polymers reduces their mechanical properties which is a …

Impact Of Stirrer Speed And Media Type-Loading On The Breakage Kinetics During Wet Stirred Media Milling Of Griseofulvin, Nathaniel Parker

Theses

The aim of this study is to investigate the impact of stirrer speed (2000-4000 rpm) and bead loading (~20-60%) on the breakage kinetics-energy consumption during milling of griseofulvin, a poorly soluble drug, and compare the performance of crosslinked polystyrene (CPS) beads with that of yttrium-stabilized zirconia (YSZ) beads. Laser diffraction, SEM, viscometry, and XRPD were used for characterization. A microhydrodynamic model was used to interpret the breakage kinetics. An increase in stirrer speed led to faster breakage due to more frequent and forceful CPS bead-bead collisions. Despite causing slight decrease in maximum contact pressure, an increase in CPS bead loading …

Effect Of 3d Printed Tablet Shape On Drug Release Profile, Christina Gedeon

Theses

There is a growing interest in utilizing additive manufacturing (AM) as a manufacturing tool to develop oral tablets for personalized medicine. This ultimate goal in mind, this study explores the feasibility of extrusion-based fused deposition modeling (FDM) to 3D print oral tablets with tunable design to control drug release profile. Tablets are printed using poly(vinyl alcohol) (PVA) loaded with model drugs: acetaminophen and caffeine. Hot melt extrusion (HME) is used to fabricate PVA filaments loaded with acetaminophen and caffeine. These filaments are used to fabricate a range of tablets with varying designs to prepare immediate and delayed release tablets. Thermal …

Glass Transition Temperature Of Particles For Drug Delivery, Yiqing Yang

Theses

Drug delivery plays an important role in targeted therapies and nanoparticles which can be used as drug carriers and it’s a frequently researched topic. Poly(lactic-co-glycolic acid) (PLGA), a highly biocompatible polymer, has been used as a drug delivery vehicle in many studies. One of the challenges facing drug delivery particles is the problem of burst release which is when a large amount of the drug is suddenly released from the particle once it is placed in the body. This is generally undesirable as usually a slow and controlled release is preferred. The glass transition temperature has an effect on drug …

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman

Theses

Njs, the minimum agitation speed needed to just suspend all the solid particles in a solid-liquid mixture stirred in an agitated vessel, is a critical parameter to properly operate industrial tanks in a large number of industrial operations. As a result, a significant literature on Njs is available. The oldest and the most common method to measure Njs experimentally is that of Zwietering’s (Chem. Eng. Sci., 1958, 8, 244-253), where Njs can be visually obtained by determining when the solids stay at the bottom of the tank for no more than 1-2 seconds before being swept away. Although this has …

Production Of Anti-Corrosion Materials From Uae Date Palm Waste, Nour Shehadeh Abdelrahman

Theses

Palm tree serves as the main source of biomass in the Gulf countries. The United Arab Emirates (UAE) alone is blessed with more than 40 million date palm trees, which generate a huge amount of waste annually. The main objective of this thesis is to examine the ability to produce a corrosion inhibitor from a date palm tree, waste, starting by extracting lignin from different parts of the date palm tree and characterizing the extracted lignin, converting lignin to sodium lignosulfonate, while selecting the optimum condition for the conversion reaction and characterizing the prepared lignosulfonate. Finally, the corrosion efficiency for …

Development Of Biodegradable -Polylactic Acid - Date Palm Waste Composite As Thermal Insulation Material, Mohamed Saeed Barkhad

Theses

This study aims to develop a green polymer composite from local natural waste, such as date pit powder (DPP) and date palm wood powder (DPWP), as an insulating material. The recycling and reuse of natural waste as filler for green insulation materials has many significant benefits for the environment of the UAE.

Date palm waste was mixed with a polylactic acid (PLA) polymer with various proportions in a melt extruder. The mixtures produced were then shaped differently after testing in a thermal compression machine. These composites were tested to evaluate their physical (water absorption, chemical resistance, and bulk density), thermal …

Investigating Green Inhibitors For Acidic Corrosion Of Carbon Steel, Osama Abu-Alyosr Kamal Ibrahim

Theses

This study is intended to investigate Khalas palm date pits extract as a green corrosion inhibitor alternative to commercial inhibitors. Inhibition efficiency of the obtained extract was investigated on carbon steel grade S355JR immersed in different corrosive mediums of 2 molarity hydrochloric acid (𝐻𝐶𝑙) solution and seawater solution. Along with other ingredients in palm date pits, Polyphenolic compounds have a significant anti-oxidation property and were found effective in reducing corrosion rate.

Due to its common industrial applications, Carbon steel was used in this investigation as the corroding medium, while 2M 𝐻𝐶𝑙 and seawater solutions were used separately as the corrosive …

Feasibility Of Integrating Microfluidics Into Point-Of-Care Bio-Diagnostics, Swetha Manoharan

Theses

Potassium in the body needs to be maintained in proper levels for the normal functioning of heart and kidneys. The aim of this work is to develop a simple technique to measure the concentration of Potassium present in a bodily fluid sample, which can be used to assess the health condition of extremely sick patients, especially when the patient's condition needs to be diagnosed and results needs to be obtained rapidly under Point-of-Care settings. Microfluidics is one of the platforms used in bio-diagnostics because of several advantages such as low sample volume requirement and integration into high-throughput screening. In this …

Interactions Between Polymer Nanoparticles And Blood Plasma Applied To Drug Delivery Systems, Mark Bannon

Theses

Targeted nanoparticle drug delivery has the potential to replace current forms of cancer therapy with previously unparalleled efficiency. Upon introduction into the human body, nanoparticles exhibit a substantial increase in diameter due to a biomolecular corona formation caused by interactions between blood plasma proteins and the nanoparticles. These interactions must be analyzed and understood for targeted delivery to reach its potential in both feasibility and efficiency.

To study the formation of the protein corona, polystyrene nanoparticles were incubated in vitro in goat blood plasma for 10-minute intervals, diluted to different degrees and then measured to obtain the hydrodynamic diameter of …

Mechanochemical Nitration Of Aromatic Compounds, Oleg Shlomo Lagoviyer

Theses

Aromatic compounds such as toluene are commercially nitrated using a combination of nitric acid with other strong acids. This process relies on the use of highly corrosive chemicals and generates environmentally harmful waste, which is difficult to handle and dispose of. In this study aromatic nitration using solvent-free mechanochemical processing of environmentally benign precursors has been achieved and investigated. Mononitrotoluene was synthesized by milling toluene with sodium nitrate and molybdenum trioxide as a catalyst. Several parameters affecting the desired product yield and selectivity were identified and varied. MNT yields in excess of 60% have been achieved in different tests. The …

Optimization Of A New Array Noise Tool; Analysis & Interpretation Of Case Studies Of Down- Hole Leak Detection, Moustafa Mahmoud Hassan Ismail

Theses

This thesis is concerned with the optimization and analysis of new array noise tools. Various lab and field case studies are analyzed to test the capabilities and determine the optimum operating conditions of the new tool for leak detection purposes. The purpose of this study is to optimize the logging procedure of real-time array noise tool, selecting adequate gain parameters and frequency band in the processing phase, and to analyze the data acquired through multiple labs and field tests. The study methodology involved the following steps:

1. Performing lab and field tests for the tool in a range of different …

Comparative Analysis Of The Dissolution Performance Of Aspirin Tablets In The Usp Apparatus 2 And In A Minivessel Dissolution System, Annmarie C. Walker

Theses

Dissolution testing is a critical component of quality control procedures in the pharmaceutical industry in order to ensure that the final solid dosage forms have consistent dissolution properties. Dissolution tests are also routinely conducted to evaluate the in-vitro performance of solid dosage forms during pharmaceutical development, to aid in the behavior of formulations, and to optimize drug release from dosage forms.

The use of compendial dissolution test apparatus and techniques, such as the USP 2 (Paddle), to characterize the dissolution performance of oral drug delivery system is an established area of pharmaceutical science. However, this method is not always appropriate, …