Chemical Engineering Commons^™

Specifically Adsorbed Ions In Hematite Flotation, Natalia Parra Alvarez

Dissertations, Master's Theses and Master's Reports

Specifically adsorbed ions, such as calcium and magnesium in iron ore flotation, are ions that can chemically bind with the mineral surfaces and alter the surface properties. Calcium and magnesium are unavoidable in process water and their concentrations are increasing due to water recirculation and reagent additions. These ions are detrimental to the flotation process. Calcium has always been the main focus in research, yet we found that magnesium is more detrimental in flotation due to its smaller atomic size. Starch adsorption in iron ore flotation is key for the effective depression of hematite. It has been determined by flotation, …

Kinetics Study Of The Hydrodeoxygenation Of Xylitol Over A ReoX-Pd/Ceo2 Catalyst, Blake Macqueen, Michael Royko, Bradie S. Crandall, Andreas Heyden, Yomaira J. Pagán-Torres, Jochen A. Lauterbach

Faculty Publications

In this study, we elucidate the reaction kinetics for the simultaneous hydrodeoxygenation of xylitol to 1,2-dideoxypentitol and 1,2,5-pentanetriol over a ReOx-Pd/CeO2 (2.0 weight% Re, 0.30 weight% Pd) catalyst. The reaction was determined to be a zero-order reaction with respect to xylitol. The activation energy was elucidated through an Arrhenius relationship as well as non-Arrhenius kinetics. The Arrhenius relationship was investigated at 150–170◦ C and a constant H2 pressure of 10 bar resulting in an activation energy of 48.7 ± 10.5 kJ/mol. The investigation of non-Arrhenius kinetics was conducted at 120–170◦ C and a sub-Arrhenius relation was elucidated with activation energy …

Investigating The Effect Of E30 Fuel On Long Term Vehicle Performance, Adaptability And Economic Feasibility, Adil Alsiyabi, Seth Stroh, Rajib Saha

Department of Chemical and Biomolecular Engineering: Faculty Publications

Due to the drawbacks associated with the use of petroleum derived fuels, the use of more sustainable fuel sources has garnered increasing attention in several sectors including road transportation. However, the transition away from gasoline is often hindered by the inability of currently operating vehicles to efficiently run under alternative fuels. Therefore, the logical short-term alternative is to transition to clean fuel sources including higher-ethanol fuel blends that are compatible with current fuel systems and spark-ignition engines. In this work, the long-term adaptability and economic feasibility of non-flex vehicles to consume a 30% ethanol (E30) fuel blend was investigated. Sixteen …

Periodicity In The Electrochemical Dissolution Of Transition Metals, Florian D. Speck, Alexandra Zagalskaya, Vitaly Alexandrov, Serhiy Cherevko

Department of Chemical and Biomolecular Engineering: Faculty Publications

Extensive research efforts are currently dedicated to the search for new electrocatalyst materials in which expensive and rare noble metals are replaced with cheaper and more abundant transition metals. Recently, numerous alloys, oxides, and composites with such metals have been identified as highly active electrocatalysts through the use of high-throughput screening methods with the help of activity descriptors. Up to this point, stability has lacked such descriptors. Hence, we elucidate the role of intrinsic metal/oxide properties on the corrosion behavior of representative 3d, 4d, and 5d transition metals. Electrochemical dissolution of nine transition metals is quantified using online inductively coupled …

Image Analysis Of Colloidal Systems For Pair And Triplet Correlations., Brianna Price

Electronic Theses and Dissertations

Interactions among colloidal particles drive stability of suspensions or the assembly of particles into larger superstructures such as agglomerates or crystals. Typically, colloidal interactions are modeled using pairwise interaction potential energies which consider the interactions between pairs of particles. However, additional particles can modulate pair potentials, leading models to predict incorrect behavior. To analyze the effects of three-body interactions on the structuring of colloidal systems, pair and triplet correlation functions are calculated from published experimental data. These correlation functions are then translated into empirical pair and triplet potentials of mean force, which are then used to model systems more accurately …

Electrospun Fiber Scaffolds For Engineering Glial Cell Behavior To Promote Neural Regeneration, Devan L. Puhl, Jessica L. Funnell, Derek W. Nelson, Manoj K. Gottipati, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electrospinning is a fabrication technique used to produce nano-or micro-diameter fibers to generate biocompatible, biodegradable scaffolds for tissue engineering applications. Electro spun fiber scaffolds are advantageous for neural regeneration because they mimic the structure of the nervous system extracellular matrix and provide contact guidance for regenerating axons. Glia are non-neuronal regulatory cells that maintain homeostasis in the healthy nervous system and regulate regeneration in the injured nervous system. Electro spun fiber scaffolds offer a wide range of characteristics, such as fiber alignment, diameter, surface nano topography, and surface chemistry that can be engineered to achieve a desired glial cell response …

Evaluation Of Robust Epoxy Resin Sealants For Wellbore Integrity Applications, Mohammed Mousa M Alkhamis

Doctoral Dissertations

"During the drilling and completion phases of oil and gas wells, cement is placed in the wellbore as a barrier between the casing and the formation. All casing strings must be cemented to protect and support the casing, and to isolate production zones. The primary cement must prevent the wellbore fluids from migrating in an annular flow path so as to allow the wells to be utilized without any control problems. The primary cement may fail to deliver full zonal isolation due to several reasons such as insufficient mud removal before the cementing, casing expansion, and contraction, high fluid losses, …

3d-Printed Adsorbents For Gas Separations: A Material Development, Kinetic Assessment, And Process Performance Investigation, Shane Lawson

Doctoral Dissertations

“Adsorbent materials are promising for various gas purification processes, however, forming them into structured contactors is paramount in enhancing mass transfer properties and reducing pressure losses. In this research, various adsorbents were engineered into structured contactors with 3D printing. The overall goal of this research was to improve the formulation methods of 3D-printed adsorbents and understand their performances in gas separation processes. The specific objectives were to 1) develop new adsorbent 3D-printing strategies, 2) understand the kinetic properties of printed adsorbent monoliths, and 3) assess their process performances. Objective one was addressed by developing five 3D printing techniques: i) oxide …

Cyclic Sequential Adsorption Desorption/Thermal-Catalytic Oxidation Of Volatile Organic Compounds: Material Development, Process Advancement/Improvement, And Numerical Modeling, Simulation And Optimization, Busuyi Ojo Adebayo

Doctoral Dissertations

"Volatile organic compounds (VOCs) are a group of useful organic chemicals but when emitted have contributed to air pollution. They affect human health, cause environmental degradation and contaminate our waters and soils, so they need to be controlled. When they exist in dilute concentrations, abatement becomes challenging, thus requiring advanced abatement methods, e.g., sequential adsorption desorption/thermal-catalytic oxidation process. The overall goal of this research was to abate dilute streams of VOCs via the process. The specific objectives were to 1) develop novel adsorbent/catalyst dual-function materials (DFMs) for the process, 2) improve the operability of a one-bed-one-column reactor configuration for the …

The Performance Of Tio2-Based Photocatalyst Coated Pet Films For Phi-X 174 Virus Inactivation, Purim Kusonsakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Catalyst coated films are of great interest due to their high performance, reuse, and facility in separation. TiO2 has shown high efficiency for photocatalytic reactions. In this work, the optimal coating condition and efficiencies of catalyst films on the photocatalytic oxidation reactions are shown. The results are shown that the %wt of Ti on PET film depends on the ratio of Si:Ti (amount of TEOS) resulting in the ratio of 0.14 is optimal for P25 coating due to the highest %wt Ti on film. N-doped TiO2 and 5% loading silica with TiO2 Film catalysts were coated on film, N-doped on …

Fabrication And Optimization Of Thin Film Composite Membrane Incorporated With Tio2 Nanoparticles To Enhance Anti-Fouling Property, Sasakorn Charoenyuenyao

Chulalongkorn University Theses and Dissertations (Chula ETD)

The polyamide thin-film composite (PA-TFC) membranes containing the titanium dioxide nanoparticles (TiO2 NPs) were developed to improve the membrane performances, especially the anti-fouling properties such as normalized flux and flux recovery. The selective thin-film layer was fabricated over polysulfone (PSf) through the interfacial polymerization (IP) of m-phenylenediamine (MPD) and 1,3,5-benzenetricarbonyl chloride (TMC) monomers. The response surface methodology (RSM) with Box-Behnken strategy was applied to find the optimal fabrication condition of TiO2, pH, ethyl alcohol in MPD solution that could obtain the best overall performances for the synthesized membranes. The result indicated that the addition of TiO2 NPs together with ethyl …

Influences Of Biofriendly Amino Acids On Methane Hydrate Formation For Natural Gas Storage And Transportation Application, Chuvich Chaovarin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Solidified natural gas (SNG) is an appealing option for storing natural gas in the form of clathrate hydrates. However, it has some limitations, particularly the slow rate of hydrate formation and the requirement for severe operating conditions. To overcome these constraints, one approach is to introduce promoters into the system to enhance the hydrate formation rate. Amino acids have been reported as kinetic promoters with the potential to improve methane hydrate formation. In this work, the effect of three different side-chain amino acids (L-methionine, L-leucine, and L-valine) on methane hydrate formation and dissociation was investigated in terms of kinetics and …

Synthesis Of Zinc Sulfide Nanoparticles Using Microemulsion Generated By Hydrodynamic Cavitation Method, Nachapa Choojan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Zinc Sulfite (ZnS) nanoparticles have attracted attention of researchers as a promising material for semiconductor fabrication. Their optical properties are strongly size-dependent and related to production methodology. A microemulsion technique is simple and requires less energy to produce ZnS nanoparticles. However, this technique usually results in ZnS with a wide size distribution. In this work, microemulsion technique and hydrodynamic cavitation have been effectively combined for synthesis of ZnS nanoparticles with controllable and uniform size distribution. The microemulsion system which consists of water, cyclohexane, hexanol and Triton X-100 surfactant has been prepared by incorporating hydrodynamic cavitation. Experimental results number of passages, …

High Water Vapor Permeability Ethylene-Vinyl Acetate Copolymer Composite For Fresh Holy Basil (Ocimum Sanctum L.) Packaging, Nuttinan Boonnao

Chulalongkorn University Theses and Dissertations (Chula ETD)

Fresh fruits and vegetables still respire, which causes large amount of water vapor inside the package. This results in the growth of fungal and bacterial pathogens and defection in the external appearance. To solve this problem, the packaging film with an appropriate value of gas permeability that matches the respiration rate of fresh fruits and vegetable products will be used. In this study, we produced EVA copolymer composite packaging films by melt blending EVA copolymer with diatomite and sorbitan monostearate additives and adjusted gas permeability which includes water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) to be in …

The Prediction Of Pm2.5 Dispersion In Bangkok (Pathumwan District)Using Cfd Modeling, Punyisa Chaisri

Chulalongkorn University Theses and Dissertations (Chula ETD)

City configuration, meteorological conditions and emission source are the important factors affecting the concentration and dispersion of pollutants within urban street canyon. The dispersion of PM2.5 in Pathumwan district, Bangkok which has a characteristics of street canyon was predicted using a Computational Fluid Dynamics (CFD) model. Flow and dispersion of PM2.5 were analyzed using standard k-ε turbulence model. The concentrations of PM2.5 were investigated under different conditions to demonstrate the effect of city configuration in study area, meteorological characteristics, and lockdown due to COVID-19 on PM2.5 concentration. The numerical model was validated with the measured data from the air quality …

Development Of Nonaqueous Zinc-Ion Battery Based On Manganese Dioxide Cathode, Wathanyu Kao-Ian

Chulalongkorn University Theses and Dissertations (Chula ETD)

Zinc-ion batteries (ZIBs) are considered promising candidates for large-scale applications replacing lithium-ion batteries (LIBs). ZIBs having aqueous electrolytes have many advantages being low-cost, safe, and eco-friendly. However, a number of shortcomings hinder their application e.g. self-corrosion, hydrogen evolution, and Zn dendrite-formation. To mitigate these issues, nonaqueous electrolytes i.e. organic-based and room temperature ionic liquid electrolytes have been proposed. Nevertheless, nonaqueous electrolytes are yet to be elucidated. Herein, this work identifies nonaqueous electrolytes' state of the art and develops a new nonaqueous electrolyte system for ZIBs based on a manganese dioxide (MnO2) cathode. For this purpose, Zn chemistry in nonaqueous electrolytes …

Depolymerization Of Kraft Lignin To Phenolic Compounds By Electrochemical Advanced Oxidation In Microreactor, Chawakorn Rittirong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research focuses on the depolymerization of kraft lignin to phenolic compounds that are valuable and useful in various industries. Depolymerization is performed using an electrochemical advanced oxidation process with the hydroxyl radicals. In this process, microreactors are used. It consists of a graphite anode and a stainless steel cathode. The results of the variables studied were current density (3.7 and 5.55 A/m2), residence time (100-400 s), base pH (9), the base difference (sodium hydroxide and potassium hydroxide). The experiment found that the major product is octadecamide and the minor product propyl guaiacol is increased when the current increases. On …

Investigation Of Packed Bed And Moving Bed Reactors With Benchmarking Using Advanced Measurement And Computational Techniques, Binbin Qi

Doctoral Dissertations

"Trickle bed reactors (TBR), as typical packed bed reactors (PBR), are widely used in various fields. Very limited information regarding the flow behaviors, hydrodynamic, and mathematical models in extrudate catalyst shapes, such as cylinders, trilobes, and quadrilobes, can be found in literatures because the major focus was on spherical shape. Therefore, a hybrid pressure drops and liquid holdup phenomenological model for extrudate catalyst shapes was developed based on two-phase volume averaged equations, which showed high accuracy against experimental data. The maldistribution and dynamic liquid holdup were investigated in quadrilobe catalyst using gamma-ray computed tomography. A pseudo-3D empirical model was developed …

Natural Rubber Films Reinforced With Cellulose And Chitosan Prepared By Latex Aqueous Microdispersion, Naipaporn Sutipanwihan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Plastics are one of the derived products from petroleum material, which have been used in many applications worldwide, because of their various properties. However, plastic wastes create toxic environmental pollutions and problems because of their toxic constituents and non-biodegradability. Accordingly, nature materials have been proposed as a substitute for petroleum materials for bioplastic production. Natural rubber (NR) is a product from natural, which is well-known for its high elasticity. However, there are some drawbacks such as low tensile strength and low abrasion resistance. Moreover, its applications are also limited because of its poor resistance to oil and solvents. Therefore, the …

Techno-Economic Analysis Of Monoglyceride And Diglyceride Production From Waste Cooking Oil, Napat Olarachin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Monoglycerides (MGs) and their derivatives are widely used and considered the most important group of emulsifiers. These emulsifiers can be produced from waste cooking oils (WCOs) via two-step transesterification-glycerolysis or hydrolysis-glycerolysis processes. The transesterification-glycerolysis process has the advantages in terms of a high reaction rate and a high process yield. For hydrolysis, triglycerides are converted to free fatty acids (FFA) at higher reaction temperature, but water is used as a reactant. Therefore, the separation process is not complicated. This study simulated the techno-economic comparison of four different scenarios of MG and DG production using ASPEN Plus V11 simulation software. In …

Chlorination As Drinking Water Disinfection Technique And Disinfection By Products: A Scientometric Analysis, Sapna Ramchandra Shinde, Sayali D. Apte Dr, Kanchan C. Khare Dr, Philipp Otter Mr

Library Philosophy and Practice (e-journal)

The Sustainable Development Goals (SDG) 2015, defined to achieve a better and more sustainable future, contains goal number 6 related to safe and affordable drinking water facility for all till 2030. The rural and remote areas in the developing countries predominantly face the scarcity of pathogen free drinking water leading to water borne diseases and deaths due to consumption of contaminated water indicating a need of advancement in the drinking water disinfection techniques. The paper discusses scientometric analysis of publication trends in chlorination as a popular disinfection techniques and research related to the Disinfection By Products (DBPs) that are produced …

Enhanced Heavy Oil Recovery By Low Salinity Polymer Flood Combined With Microgel Treatment, Yang Zhao

Doctoral Dissertations

“Heavy oil resources account for a large portion of the total oil reserves around the world. The target heavy oil reservoir is located on Alaska’s North Slope (ANS). Advantages of low-salinity HPAM polymer (LSP) over high-salinity polymer (HSP) were demonstrated. LSP could recover more oil with 40% less polymer consumption. No additional oil was recovered by HSP after LSP flood. The first-ever polymer flood pilot on ANS showed remarkable success regarding water cut reduction, oil production increase, delayed breakthrough, and projected oil recovery improvement. Polymer alone was insufficient to achieve satisfactory recovery as the reservoirs were highly heterogeneous. Microgels could …

Effect Of Hydrogen Co-Feeding On Ethylene Polymerization With Ziegler-Natta Catalysts With Different Amounts Of Titanium, Santhakamol Kittibanpacha

Chulalongkorn University Theses and Dissertations (Chula ETD)

Effect of hydrogen on the prepared TiCl4-MgCl2 catalysts having loading amounts of titanium was investigated via ethylene homopolymerization and ethylene/1-hexene copolymerization in slurry polymerization process. First, the catalysts were prepared to obtain different Ti loadings from 4.4 to 6.5 wt%. Then, all catalysts were characterized and tested in ethylene homopolymerization and ethylene/1-hexene copolymerization in the presence and absence of hydrogen during polymerization. It was found that hydrogen enhanced the catalyst activities on the catalyst with high Ti content (6.5 wt%) for 2.6 times and 1.9 times for ethylene homopolymerization and ethylene/1-hexene copolymerization, whereas it decreased the activity of the catalyst …

Strengthening Prestressed Concrete Bridge Girders And Building Beams With Carbon Fiber Reinforced Polymer Sheets, Herish A. Hussein, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

The effect of Carbon Fiber Reinforced Polymer (CFRP) retrofitting and concrete type on the flexural strength of prestressed concrete I-section girders used in bridges and beams in buildings is investigated. Non-linear moment-curvature relationships are predicted using an iterative algorithm for both non-retrofitted and CFRP-retrofitted prestressed concrete girder and beam cross-sections with various concrete types. Two different CFRP-retrofitting schemes are analyzed for comparing their effectiveness. It is found that although non-retrofitted beam section exhibits greater ductility, the use of CFRP retrofitting in both tension and compression regions simultaneously results in a significant increase in flexural strength. It is also found that …

Preparation Of Co-Electrodeposited Pd-Au Nanocatalyst For Methanol Electro-Oxidation, Islam M. Al-Akraa, Ahmad M. Mohammad, Yaser M. Asal, Sayed S. Abd El Rehim

Chemical Engineering

No abstract provided.

New Horizons For Processing And Utilizing Red Mud, M. Archambo

Dissertations, Master's Theses and Master's Reports

Red mud is an industrial slurry waste that is produced as a byproduct of the Bayer process for alumina. The waste is generated in large quantities, up to a ratio of 2:1 against the valued product alumina. Red mud exhibits many chemical and physical properties that categorize it as a hazardous material. Due to the addition of sodium hydroxide in processing, the pH is typically at values close to 13. Small particle size discourages separation from water for disposal, so drying red mud happens over many years.

The pH of red mud can be reduced with inexpensive reagents. Carbon dioxide …

Anaerobic Reductive Bioleaching Of Manganese Ores, Neha Sharma

Dissertations, Master's Theses and Master's Reports

The increasing demand of manganese in the industries and various hindrances in its production from low grade ores by conventional method has made it imperative for researchers around the world to develop a method of manganese extraction from low grade ores that is both environment friendly and economical. Bioleaching has shown significant potential in manganese extraction and efficiencies of extraction have been found to be 70-98% with the help of various bacteria and fungi.

This study focuses on extraction of manganese with the help of mixed bacterial strains that have been collected from their natural anaerobic environment. The extraction of …

Kinetics Of Photolysis And Photocatalytic Oxidation Of Ammonium Sulfite For Hydrogen Production, Moustafa A. Soliman, Maryam Zakaria

Chemical Engineering

The production of hydrogen via photocatalytic water splitting is one of the most promising technologies for obtaining chemical energy from direct solar energy while maintaining the least possible waste and pollutants. In this paper, we obtain the kinetic parameters necessary for the design of a photoreactor for photolysis and photocatalysis of ammonium sulfite solution. For the case of photolysis, we obtain the kinetics for the effect of changing the pH on the produced amount of hydrogen. For the case of photocatalysis, the intrinsic kinetic parameters of photocatalysis of water splitting reaction of ammonium sulfite and water in the presence of …

Analysis Of A Solar Hybrid Sulfur Ammonia Copper Oxide Thermochemical Cycle For Hydrogen Production, Moustafa A. Soliman, Abdel Moniem Abomosalam, Noran Shedid, Mohamed Othman, Toka Hatem, Marc Samer

Chemical Engineering

Solar energy conversion to hydrogen by water splitting is a promising technique because it is sustainable and environmentally friendly. One option for water splitting is through thermochemical cycles in which one of the steps is electrolytic or photocatalytic. In this paper, the economics of a thermochemical process that combines photocatalysis, photovoltaics, high temperature thermal energy and energy storage to harvest solar energy is assessed. This paper focuses on the standard hybrid sulfur ammonia thermochemical cycle (SA) in which the electrolytic step of the hydrogen production from ammonium sulfite solution is augmented by a photocatalytic step. Trying to make use of …

Multimodel Operability Framework For Design Of Modular And Intensified Energy Systems, Vitor Gazzaneo

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, a novel operability framework is introduced for the process design of modular and intensified energy systems that are challenged by complexity and highly constrained environments. Previously developed process operability approaches are reviewed and further developed in terms of theory, application, and software infrastructure. An optimization-based multilayer operability framework is introduced for process design of nonlinear energy systems. In the first layer of this framework, a mixed-integer linear programming (MILP)-based iterative algorithm considers the minimization of footprint and achievement of process intensification targets. Then, in the second layer, an operability analysis is performed to incorporate key features of …