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Articles 5131 - 5160 of 14170

Full-Text Articles in Engineering

Accumulation Of Di-2-Ethylhexyl Phthalate From Polyvinyl Chloride Flooring Into Settled House Dust And The Effect On The Bacterial Community, Samantha Velazquez, Chenyang Bi, Jeff Kline, Susie Nunez, Richard Corsi, Ying Xu, Suzanne L. Ishaque Jan 2019

Accumulation Of Di-2-Ethylhexyl Phthalate From Polyvinyl Chloride Flooring Into Settled House Dust And The Effect On The Bacterial Community, Samantha Velazquez, Chenyang Bi, Jeff Kline, Susie Nunez, Richard Corsi, Ying Xu, Suzanne L. Ishaque

Mechanical and Materials Engineering Faculty Publications and Presentations

Di-2-ethylhexyl phthalate (DEHP) is a plasticizer used in consumer products and building materials, including polyvinyl chloride flooring material. DEHP adsorbs from material and leaches into soil, water, or dust and presents an exposure risk to building occupants by inhalation, ingestion, or absorption. A number of bacterial isolates are demonstrated to degrade DEHP in culture, but bacteria may be susceptible to it as well, thus this study examined the relation of DEHP to bacterial communities in dust. Polyvinyl chloride flooring was seeded with homogenized house dust and incubated for up to 14 days, and bacterial communities in dust were identified at …

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Optimization And Cost Comparison Of Reactor Types In A Styrene Production Process, Claire Lenore Cozadd Jan 2019

Optimization And Cost Comparison Of Reactor Types In A Styrene Production Process, Claire Lenore Cozadd

Honors Theses

The focus of this thesis is to use the equivalent annual operating costs of isothermal, adiabatic, and packed bed reactors in order to determine which reactor is most cost effective in a styrene production process. In order to understand the steps leading up to this comparison, background information is first given regarding chemical engineering design, optimization, and process simulation. This information was necessary for completing the ChE 451 design project, which was to analyze the base case styrene process before optimizing it, in fall 2018. The results of this project are briefly outlined in the second section. The third section …

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Discrete Optimization Of A Styrene Production Process, Seth Gray Jan 2019

Discrete Optimization Of A Styrene Production Process, Seth Gray

Honors Theses

This thesis will outline the two phases of my capstone design project for Chemical Engineering. The first goal was to simulate a styrene production process in Excel alongside my group members in ChE 451. During this phase, we looked at startup of the process and the first 12 years of operation. After the base case which included an isothermal reactor, the decision was made to switch to an adiabatic reactor based on net present value evaluations. Discrete optimization took place on the adiabatic reactor and the subsequent process. The second phase of my capstone project was the portion assigned to …

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Techno-Economic Optimization And Environmental Life Cycle Assessment Of Microgrids Using Genetic Algorithm And Artificial Neural Networks, Prashant Nagapurkar Jan 2019

Techno-Economic Optimization And Environmental Life Cycle Assessment Of Microgrids Using Genetic Algorithm And Artificial Neural Networks, Prashant Nagapurkar

Doctoral Dissertations

"This dissertation focuses primarily on techno-economic optimization and environmental life cycle assessment (LCA) of sustainable energy generation technologies. This work is divided into five papers. The first paper discusses the techno-economic optimization and environmental life cycle assessment of microgrids located in the USA using genetic algorithm. In this paper, a methodology was developed that assessed the techno-economic and environmental performance of a small scale microgrid located in US cities of Tucson, Lubbock and Dickinson. Providing uninterrupted power the microgrid was composed of seven components -- solar photovoltaics, wind-turbines, lead acid batteries, biodiesel generators, fuel cells, electrolyzers and H2 tanks. …

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Studies Related To Chemical Changes In Biochar. I. Polyacrylonitrile Internal Standard To Assess Chemical Changes In Graphene Oxide. Ii. Ultrasonic Effects On Polycyclic Aromatic Hydrocarbons As Models For Biochar, Kaci B. Crawford Jan 2019

Studies Related To Chemical Changes In Biochar. I. Polyacrylonitrile Internal Standard To Assess Chemical Changes In Graphene Oxide. Ii. Ultrasonic Effects On Polycyclic Aromatic Hydrocarbons As Models For Biochar, Kaci B. Crawford

Honors Theses

Biochar has become an increasing area of research due to its reactive edges from stacks of graphene clusters. One particular area of interest in biochar is because it is a potent soil amendment which reduces soil acidity and can reduce greenhouse gas emissions from plants. Also, chemically-modified biochar is being studied as a carbon storage method to potentially mitigate climate change. In order to understand the chemistry that takes place on biochar’s reactive edges during modification, a standard is essential. This research attempted to identify an internal standard that could be added to biochar samples to quantify chemical changes by …

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Effects Of Seawater On Carotenoid Production And Lipid Content Of Engineered Saccharomyces Cerevisiae, Yuqi Guo, Shangxian Xie, Joshua Yuan, Katy Kao Jan 2019

Effects Of Seawater On Carotenoid Production And Lipid Content Of Engineered Saccharomyces Cerevisiae, Yuqi Guo, Shangxian Xie, Joshua Yuan, Katy Kao

Faculty Publications

The use of seawater in fermentation can potentially reduce the freshwater burden in the bio-based production of chemicals and fuels. We previously developed a Saccharomyces cerevisiae carotenoids hyperproducer SM14 capable of accumulating 18 mg g−1 DCW (DCW: dry cell weight) of β-carotene in rich media (YPD). In this work, the impacts of seawater on the carotenoid production of SM14 were investigated. When using nutrient-reduced media (0.1× YNB) in freshwater the β-carotene production of SM14 was 6.51 ± 0.37 mg g−1 DCW; however in synthetic seawater, the production was increased to 8.67 ± 0.62 mg g−1 DCW. We found that this …

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Ethanol Dehydration Over Wo3/Tio2 Catalysts Using Titania Derived From Sol-Gel And Solvothermal Methods With Palladium Modification, Anchale Tresatayawed Jan 2019

Ethanol Dehydration Over Wo3/Tio2 Catalysts Using Titania Derived From Sol-Gel And Solvothermal Methods With Palladium Modification, Anchale Tresatayawed

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the characteristics and catalytic activity of WO3/TiO2 prepared by sol-gel and solvothermal and their metal modified were investigated. The research was divided into two parts. In the first part, the catalyst performance of WO3/TiO2 catalysts using titania derived from sol-gel and solvothermal methods over ethanol dehydration reaction was examined. The results showed that the different preparation methods essentially altered the physicochemical properties of TiO2 supports. It revealed that the titania derived from solvothermal method denoted as TiO2-SV exhibited higher surface area and pore volume, and larger amounts acid sites than the one obtained from sol-gel method (TiO2-SG). …

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Development Of Bioplastic Blown Films To Be Used As A Packaging For Dried Banana, Apinya Wongthanaroj Jan 2019

Development Of Bioplastic Blown Films To Be Used As A Packaging For Dried Banana, Apinya Wongthanaroj

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to study effects of poly(butylene adipate-co-terephthalate) (PBAT) contents on properties of polylactic acid / poly(hydroxybutyrate-co-hydroxyvalerate) / poly (butylene adipate-co-terephthalate) (PLA/PHBV/PBAT) blends to be used as a packaging for solar-dried bananas. The blend of PLA and PHBV (PLA/PHBV) was fixed at weight ratio of 80/20 while the PBAT content was varied from 0-30 wt%. The films were prepared by melt compounding and blown film extrusion. It was found that the addition of PBAT decreased barrier properties of PLA/PHBV film. Gas barrier which is oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) increased with increasing of PBAT …

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Production Of Activated Carbonaceous Catalyst For Their Application In Bio Jet-Fuel Synthesis, Araya Smuthkochorn Jan 2019

Production Of Activated Carbonaceous Catalyst For Their Application In Bio Jet-Fuel Synthesis, Araya Smuthkochorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Recently, research and development in alternative aviation fuel to replace fossil-based fuel has been of interest for many research works. Hydrodeoxygenation (HDO) is one of the most efficient processes to produce clean fuel. This study involves the synthesis of activated carbon (AC) from heavy fuel oil (HFO) via the carbonization-chemical activation process for utilization as catalyst support. AC with a high surface area of 1527.4 m2/g was obtained from KOH-activation in the ratio of 1:1 and carbonization temperature of 700°C. The molybdenum phosphide (MoP) catalyst impregnated on AC was prepared via the wet impregnation process. The microscopic analysis revealed the …

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Solar Energy Management System For Stand-Alone Application : Analysis Of Power Management Strategies Under Different Solar Irradiance Profiles, Chacrit Lerdwithayaprasit Jan 2019

Solar Energy Management System For Stand-Alone Application : Analysis Of Power Management Strategies Under Different Solar Irradiance Profiles, Chacrit Lerdwithayaprasit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Clean power generation from various renewable energy sources has been gaining much attention due to sustainable and environmental reasons. As renewable energy sources and power demand vary, a hybrid power system and proper energy management are required. This study is focused on the development of an energy management system (EMS) in the hybrid renewable energy system consisting of photovoltaic cell (PV), proton exchange membrane fuel cell (PEMFC), and proton exchange membrane electrolysis cell (PEMEC). A vanadium redox flow battery (VRFB) as energy storage for long-term operation is integrated into such a hybrid system. The models of each subsystem are developed …

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Co-Electrodeposition Of Gold Nanoparticle And Reduced-Graphene Oxide In Application Of Achetylcholinesterase Biosensor, Chiranthanin Mahayotheecharak Jan 2019

Co-Electrodeposition Of Gold Nanoparticle And Reduced-Graphene Oxide In Application Of Achetylcholinesterase Biosensor, Chiranthanin Mahayotheecharak

Chulalongkorn University Theses and Dissertations (Chula ETD)

A rapid pesticide detection technique is highly desirable due to the widespread usage of many pesticides in the agricultural industry. An emerging technique that shows promising potential is an electrochemical biosensor. The technique allows sensitive and rapid quantification of an analyte. Due to its simplicity, it could be a potential alternative to traditional method. In this work, we utilised a composite materials consist of partially reduced graphene oxide (rGO) and gold nanoparticle (AuNPs) to fabricate a disposable AChE biosensor on a Screen-Print Carbon electrode. The composite rGO and AuNPs possess high electron conductivity while AuNPs also exhibit desirable biocompatibility. The …

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Mechanism And Reaction Pathways Of Co2 And Hco3-Photoreduction To Hydrocarbons, Duangthip Sattayamuk Jan 2019

Mechanism And Reaction Pathways Of Co2 And Hco3-Photoreduction To Hydrocarbons, Duangthip Sattayamuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

CO2/HCO3- photocatalytic reductions in water, using P25 Titanium dioxide, produce gas products at the order of the following rate: CO>H2>CH4, using bicarbonate as a substrate, reduction rates are ca. 5 times faster than using CO2 due to the adsorption constant of CO2 on the TiO2 surface is smaller than the bicarbonate. Langmuir-Hinshelwood kinetic model was used to describe the mechanism; therefore, adsorption constant (K) and the rate of maximum substrate coverage (k) at different charges of P25-surface were readily obtained. The K constant of TiO2-adduct formation favors no charge surface but k constant favors positive charge surface. Most …

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Modeling Aromatics Production From Mixtures Of Butanes And Butenes With Chemical Equilibria, Hataipat Sangwattanakul Jan 2019

Modeling Aromatics Production From Mixtures Of Butanes And Butenes With Chemical Equilibria, Hataipat Sangwattanakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aromatics production from C4 hydrocarbons is an interesting way to increase economic values and mixed C4 usage alternatives. This study was to model aromatics production from mixtures of butanes and butenes, enabling industrial work to be more developed and actualized by reducing laboratory cost and experimental time. The model was regarded as an equilibrium state in which the forward reaction rate and the reverse reaction rate are equivalent. The catalysts would be Zn loaded on ZSM-5/ZSM-11 under 480 ⁰C and 0.4 MPa and MoC loaded on HZSM-5 under 500 ⁰C and 1 atm. The reactions in the models were from …

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Preparation Of Natural Rubber Powder Modified With Bis(Triethoxysilylpropyl)Tetrasulfide Treated Silica By Spray Drying Process, Intira Boonvisood Jan 2019

Preparation Of Natural Rubber Powder Modified With Bis(Triethoxysilylpropyl)Tetrasulfide Treated Silica By Spray Drying Process, Intira Boonvisood

Chulalongkorn University Theses and Dissertations (Chula ETD)

In polymer industry, Natural rubber powder (NRP) is broadly used because of its stability and useability. Although, NRP is difficult to be produced due to the rubber adhered together. Consequently, silica was used to encapsulated the rubber particle to avoid adhesion of rubber. However, there is a polarity difference between silica and rubber. Silica can be made hydrophobic via surface modification with silane coupling agent, bis[3-(triethoxysilyl)propyl]tetrasulfide (TESPT). This research study aimed to prepare uniform silica-coated NRP via a combination of silane modification and spray drying technique. The effect of the mass ratio of TESPT and silica is 1%, 5%, 8%, …

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Iodine Encapsulation Using Anionic Polyelectrolytes For Rechargeable Zinc-Iodine Batteries, Jirapha Pimoei Jan 2019

Iodine Encapsulation Using Anionic Polyelectrolytes For Rechargeable Zinc-Iodine Batteries, Jirapha Pimoei

Chulalongkorn University Theses and Dissertations (Chula ETD)

Rechargeable zinc-iodine batteries are attractive as promising candidates for electrical energy storage due to their abundant resources, low cost, and high safety. However, these batteries still have some problems, such as poor cycling stability and high self-discharge due to the leakage of iodine species from the positive electrode. Anionic polyelectrolytes can be applied as supportive binders to alleviate this issue because these polyelectrolytes can encapsulate iodine species and facilitate the transfer of other active species. In this study, different types of anionic polyelectrolytes, including sodium carboxymethyl cellulose (Na-CMC), sodium alginate (Na-Alg), and sodium polystyrene sulfonate (Na-PSS), were investigated. The batteries …

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Single-Step Conversion Of Xylose To Furfural And Furfuryl Alcohol On Zeolite-Based Catalyst, Jirapat Chatkaweekoon Jan 2019

Single-Step Conversion Of Xylose To Furfural And Furfuryl Alcohol On Zeolite-Based Catalyst, Jirapat Chatkaweekoon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Furfural possesses the potential to be utilized as a platform compound for the synthesis of a wide variety of chemicals, especially furfuryl alcohol, which is an important intermediate used to produce high-value chemicals. In this research, several types of zeolite catalysts in hydrogen form are used as catalysts for conversion of xylose to produce furfural and furfuryl alcohol in one step. The reaction is carried out under 130°C, 30 bar hydrogen pressure, and 2 h reaction time. Acid site types (Lewis and Bronsted) are important for the catalysis and distribution of the product. Bronsted acid sites promote xylose dehydration to …

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Catalytic Dehydration Of Ethanol With Different Loading Of Wo3 Supported On Activated Carbon And Clay Catalysts, Jirayu Liewchalermwong Jan 2019

Catalytic Dehydration Of Ethanol With Different Loading Of Wo3 Supported On Activated Carbon And Clay Catalysts, Jirayu Liewchalermwong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The catalytic ethanol dehydration is a reaction, which increases the value of ethanol by producing diethyl ether (DEE) or ethylene. The catalysts which have been used for this reaction were tungsten catalysts supported on activated carbon and montmorillonite catalysts, by varying W loading between 2-13.5 wt.%. The catalysts were tested in a fixed bed microreactor under atmospheric pressure and temperature range of 200 to 400˚C. The results showed that Low tungsten on catalyst decreased the total surface acidity. Besides, additional tungsten loading increased the total surface acidity. Low tungsten loading enhanced ethanol dehydrogenation to acetaldehyde. The high content of tungsten …

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Effects Of Cuo/Zno/Al2o3 Catalyst Modification Using Zr, Mn And Si For Methanol Synthesis Via Co2 Hydrogenation, Kamonlak Pongpanumaporn Jan 2019

Effects Of Cuo/Zno/Al2o3 Catalyst Modification Using Zr, Mn And Si For Methanol Synthesis Via Co2 Hydrogenation, Kamonlak Pongpanumaporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Currently, the estimated CO2 amount has tended to increase interesting of population. One of the most effective utilization ways of CO2 is to convert CO2 to higher valued chemicals. Thus, methanol was chosen to produce via CO2 hydrogenation by using CuO/ZnO/Al2O3 (CZA) catalyst. In the first part, CZA was prepared by co-impregnation method under different pH (7, 8 and 9) during co-precipitation. It was found that the suitable pH was 8 (CZA-PH8) due to high surface area, high basicity, and reducibility. The CO2 conversion and methanol selectivity were 2.6% and 10%, respectively at 250oC under atmospheric pressure. However, it should …

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Deactivation Of Ti-Based And Γ-Al2o3 Catalysts In Liquid-Phase Methyl Oleate Epoxidation Reaction, Kanokpon Maungthong Jan 2019

Deactivation Of Ti-Based And Γ-Al2o3 Catalysts In Liquid-Phase Methyl Oleate Epoxidation Reaction, Kanokpon Maungthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

To eliminate some drawback of heterogeneous catalysts as a low stability, the deactivation scheme and surface regeneration of TiO2 (P25), TS-1 and γ-Al2O3 catalysts was investigated on the liquid-phase methyl oleate epoxidation reaction at 50 ºC. Based on the results, there are two deactivation effects illustrated on the surface after the reaction: (1) the fouling effects are found the main deactivation on this reaction. There are three types which type 1 is found in P25 and γ-Al2O3, type 2 is uncovered in TS–1 and γ-Al2O3, and type 3 is appeared in γ-Al2O3 only. The FT-IR reveals that are alkane (C–H) …

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Development Of Stack Model For Tri-Electrode Rechargeable Zinc-Air Cylindrical Flow Battery, Kanya Bumroongsil Jan 2019

Development Of Stack Model For Tri-Electrode Rechargeable Zinc-Air Cylindrical Flow Battery, Kanya Bumroongsil

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, the demand for renewable energy is continuously increasing. Therefore, an efficient energy storage system is essential. Zinc-air batteries have received extensive attention because they use low-cost material but offer great safety benefits. This research, therefore, develops a stack model for a tri-electrode tubular designed rechargeable zinc-air flow battery for using in a large scale system. The connection of battery cells in series and parallel is studied. The connection of battery cell with common flowing electrolyte creates a shunt current. A mathematical model is developed and validated against experimental data, which measured both full cell and half cell potentials. The …

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A Study On The Deactivation Of Nickel-Based Catalyst For The Dry Reforming Of Methane Via Density Functional Theory, Mongkol Lerdpongsiripaisarn Jan 2019

A Study On The Deactivation Of Nickel-Based Catalyst For The Dry Reforming Of Methane Via Density Functional Theory, Mongkol Lerdpongsiripaisarn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, the stability assessment of catalyst for the dry reforming reaction was investigated through the coke resistance performance and the ability of coke removal. The coke resistance performance was considered via the coke adsorption energy. For surface 100 and 211, NiCo bimetallic catalyst and Ni exhibit weaker bonding between coke and catalyst surface. For surface 111, both catalysts exhibited similar adsorption energy value. NiCo bimetallic catalyst also showed higher adsorption energy for surface 111 and 211 than the noble metal catalyst such as Rh and Pd catalyst which means NiCo catalysts can show the coke resistance performance that …

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Study Of Thermal And Mechanical Properties Of Tertiary Blend Of Poly(Lactic Acid), Poly(Hydroxybutyrate-Co-Hydroxyvalerate) And Thermoplastic Starch, Naphat Yampry Jan 2019

Study Of Thermal And Mechanical Properties Of Tertiary Blend Of Poly(Lactic Acid), Poly(Hydroxybutyrate-Co-Hydroxyvalerate) And Thermoplastic Starch, Naphat Yampry

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, single-use plastics such as straws, plastic bags cause plastic waste problems because the majority of these plastics which are petroleum-based plastics are not compostable and difficult to recycle. As a result, biodegradable plastic is a proper option to replace traditional plastic. The objective of this work was to study the morphology as well as the thermal and mechanical properties of tertiary blend of poly(lactic acid) (PLA), poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and thermoplastic starch (TPS). PLA/PHBV at weight ratios of 80/20, 70/30, and 60/40 were prepared to find the optimal ratio. Then the PLA/PHBV at weight ratio of 80/20 was added by …

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Development Of Zero-Waste Package For Asphalt From Natural Rubber / Ethylene Vinyl Acetate Copolymer Thermoplastic Vulcanizates, Nappaphan Kunanusont Jan 2019

Development Of Zero-Waste Package For Asphalt From Natural Rubber / Ethylene Vinyl Acetate Copolymer Thermoplastic Vulcanizates, Nappaphan Kunanusont

Chulalongkorn University Theses and Dissertations (Chula ETD)

Asphalt is normally delivered in liquid form which was heated all the time. It consumes more energy and need the special truck to deliver it. An alternative way to deliver the asphalt in form of solid covered with package can reduce energy consumption and normal truck can be used to deliver. The objective of this research was to develop the zero-waste package for asphalt that was no waste after use and not harmful to asphalt properties. The research consists of two parts which are (1) development of package from natural rubber (NR) and ethylene vinyl acetate copolymer (EVA) thermoplastic vulcanizates …

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Improvement And Economic Analysis Of Bio-Hydrogenated Diesel Production For Producing Bio-Jet Fuel, Nattamon Munkong Jan 2019

Improvement And Economic Analysis Of Bio-Hydrogenated Diesel Production For Producing Bio-Jet Fuel, Nattamon Munkong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, process improvement of bio-hydrogenated diesel (BHD) production to produce jet fuel as an alternative product was carried out. The BHD was produced from palm oil with NiMo/Y-Al2O3 catalyst, while the bio-jet fuel was produced by catalytic cracking of the BHD product using NiAg/SAPO-11 catalyst, followed by appropriate separations. Process simulation by using Aspen Plus program was performed to evaluate the improved process. A comparison with a base case BHD production process was also demonstrated and discussed. It was found that a conventional existing BHD process can be improved by plugging in a hydrocracking/isomerization unit to process. The …

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Study Of Co2 And Bi-Reforming Of Methane On Modified Nickel-Based Catalysts, Nichakorn Buasuk Jan 2019

Study Of Co2 And Bi-Reforming Of Methane On Modified Nickel-Based Catalysts, Nichakorn Buasuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, several currently operated industrial factories significantly increase the rate of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) far higher than those that should be normally. Therefore, various mitigation ways to reduce carbon dioxide and methane are increasingly important. The prevailing methods are dry reforming of methane and bi-reforming of methane. Therefore, this research involves the study of the catalytic activity and coke resistance on the Ni-based catalysts with and without a promoter. The activity tests on the dry reforming of methane reaction and bi-reforming of methane reaction were performed in a fixed-bed reactor under atmospheric pressure at …

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Development And Characterization Of Natural Rubber-Cellulose Sponge, Nuttapon Suppanucroa Jan 2019

Development And Characterization Of Natural Rubber-Cellulose Sponge, Nuttapon Suppanucroa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Natural rubber (NR) sponges are a renewable biopolymer material derived from milky sap (latex) from rubber trees. In this study, composite sponges of natural rubber and cellulose (NR-C) with various compositions were synthesized. The Dunlop process was employed to prepare the NR-C sponges in various contents of cellulose fibers as reinforcing agent. The cellulose fibers were extracted from the pulp of eucalyptus trees and sodium alginate (SA) was used as dispersing agent. The aim of this work was to develop a green composite sponge with highly porous, flexible, and hydrophilic properties. The effects of cellulose loading on mechanical performance of …

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Application Of Co-Solvent For Biodiesel Production In Ultrasound-Assisted Reactor, Panidaporn Ritprasert Jan 2019

Application Of Co-Solvent For Biodiesel Production In Ultrasound-Assisted Reactor, Panidaporn Ritprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Biodiesel has been a promising alternative energy due to its renewability and lesser emissions of harmful gases such as carbon monoxide in comparison to traditional petroleum diesel fuel. Mostly, biodiesel production via transesterification requires catalyst to achieve faster reaction rate and complete the reaction. However, mass transfer between two immiscible reactants are obstacle to the biodiesel production. In this work, ultrasound-assisted (US) reactor and addition of co-solvent were used to overcome mass transfer limitation. The condition for biodiesel production from transesterification of palm oil using a circulated US reactor and addition of co-solvent was operated at 60°C, 1 atm, calcium …

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Improvement Of Screen Printable Anisotropic Conductive Adhesive With Polyethylene Glycol As Diluent, Papitchaya Manduang Jan 2019

Improvement Of Screen Printable Anisotropic Conductive Adhesive With Polyethylene Glycol As Diluent, Papitchaya Manduang

Chulalongkorn University Theses and Dissertations (Chula ETD)

The primary aim of this research is to improve screen printable anisotropic conductive adhesive by reducing the viscosity of anisotropic conductive adhesive which is EPN/PPGDE/CTBN epoxy adhesive with polyethylene glycol 400. This research compared the conductivity of commercial and synthesized silver particles. As a result, the volume resistivity of commercial silver particles was lower than the synthesized silver particle due to silver oxide of silver particles. 1 phr of commercial silver particle was added in anisotropic conductive adhesive in which its volume resistivity was less than 1 Ω·cm. The effect of addition polyethylene glycol in the anisotropic conductive adhesive with …

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Development And Characterization Of Solid Oxide Electrolysis Cells Based On Zirconia And Ceria Based Electrolyte For Hydrogen Production From Steam, Parintorn Temluxame Jan 2019

Development And Characterization Of Solid Oxide Electrolysis Cells Based On Zirconia And Ceria Based Electrolyte For Hydrogen Production From Steam, Parintorn Temluxame

Chulalongkorn University Theses and Dissertations (Chula ETD)

Steam electrolysis for hydrogen production is investigated in solid oxide electrolysis cell (SOEC). Sc3+, Ce4+, and Gd3+ are doped in zirconia (SCGZ) and compared with yttria stabilized zirconia (YSZ) and gadolinium doped ceria (GDC) electrolyte. Electrolyte-supported cells are fabricated. The SCGZ and YSZ electrolytes are dense with >95% relative density while GDC is less densified. The activation energy of conduction of the SCGZ electrolyte is the lowest at 65.58 kJ mol-1 although phase transformation is detected after electrolyte fabrication process. Cathode-supported cell having SCGZ electrolyte (Ni-SCGZ/SCGZ/BSCF) shows the highest electrochemical performance. Durability test of the cells in electrolysis mode is …

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Biodiesel Production From Cooking Palm Oil In The Presence Of Cao/Γ-Al2o3 Catalyst Using Rotating Packed-Bed Reactor, Patcharaporn Sukjarern Jan 2019

Biodiesel Production From Cooking Palm Oil In The Presence Of Cao/Γ-Al2o3 Catalyst Using Rotating Packed-Bed Reactor, Patcharaporn Sukjarern

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis proposed the biodiesel production from cooking palm oil by using rotating pack bed reactor (RPB). The experiments were divided into 3 parts i) preparation of CaO/γ-Al2O3 catalyst and catalytic activity for the transesterification in a conventional mechanical stirrer reactor (MS). ii) study of CaO/γ-Al2O3 heterogeneous catalysts using RPB iii) study of NaOH homogeneous catalysts using RPB by packing inert packing bed. The Response surface methodology (RSM) based on the Central composite design (CCD) was used to reduce the number of experiments. The optimum condition for CaO /γ-Al2O3 catalyst preparation was at calcination temperature of 500ºC and 24%CaO/γ- Al2O3. …

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