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Microemulsion Formation Of Vegetable Oils Using Mixed Extended Surfactant For Cleaning Applications, Siriluk Jariyawattanarat
Microemulsion Formation Of Vegetable Oils Using Mixed Extended Surfactant For Cleaning Applications, Siriluk Jariyawattanarat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Some vegetable oils and animal fats can form semi-solid crystalline. The formation of semi-solid fats or waxy soils results in weak interactions between the oil and surfactant during the cleaning process. In this study, the anionic extended surfac-tant (C14-15, 8PO-SO4) systems were employed to form a middle phase microemul-sion with various vegetable oils (coconut, palm and soybean oil). The addition of nonionic extended surfactant (C16-18, 2PO-4EO-OH) in the mixed surfactant systems was also evaluated to observe the solubility enhancement of oil and water phase. The IFT value of formulated surfactant systems was measured to determine the optimum salinity. The Hydrophilic-Lipophilic …
Synthesis Of Magnetic Carbon Nanoparticles Using Pyrolysis Of Glycerol And Ferrocene For Antibiotic Removal, Konrat Kerdnawee
Synthesis Of Magnetic Carbon Nanoparticles Using Pyrolysis Of Glycerol And Ferrocene For Antibiotic Removal, Konrat Kerdnawee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Synthesis of magnetic carbon nanoparticles (M-CNPs) via nebulizing co-pyrolysis of glycerol and ferrocene with magnetic induction was successfully conducted. Experimental investigation on influence of synthesizing temperature and ratio of glycerol to ferrocene suggested that at 800 °C of synthesizing temperature with an initial weight ratio of glycerol to ferrocene of 3:1, the highest M-CNP synthesizing yield of 15.9 % was achieved. With the presence of magnetic induction, controlled synthesis of M-CNPs could be anticipated as a promising method for producing M-CNPs with high quality and high yield. Oxy-tetracycline (OTC) has been recognized as environmental contamination due to its over-dosage and …
Development Of Conductive Polyimide/Polysulfone Composites As Positive Temperature Coefficient Materials, Noppawat Kuengputpong
Development Of Conductive Polyimide/Polysulfone Composites As Positive Temperature Coefficient Materials, Noppawat Kuengputpong
Chulalongkorn University Theses and Dissertations (Chula ETD)
For positive temperature coefficient (PTC) applications of electrically conductive composites, volume resistivity at room temperature of lower than 104 Ω.cm is one major requirement. Conductive polyimide (PI) PTC with the above level of conductivity value can be achieved by a use of carbon black (CB) as conductive filler. For materials with PTC, there is a change in resistance related to temperature. In order to reduce the amount of CB used in the PTC composites, one of well-known methods is to introduce another polymer into a polymer to generate immiscible blends. When the conductive filler is dispersed in one polymer phase, …
Performance Evaluation Of Integrated Co2 Huff-N-Puff And Wag In Low-Pressure Heterogeneous Reservoir, Hutthapong Yoosook
Performance Evaluation Of Integrated Co2 Huff-N-Puff And Wag In Low-Pressure Heterogeneous Reservoir, Hutthapong Yoosook
Chulalongkorn University Theses and Dissertations (Chula ETD)
The integrated CO2 Huff-n-Puff and WAG is a novel technique to combine CO2 Huff-n-Puff technique that conducted at early state and followed by WAG technique until the end of operating time. This technique is effectiveness in term of increased oil recovery and reduced CO2 utilization. However, the integrated CO2 Huff-n-Puff and WAG process contains numerous adjustable operating parameters. Hence, numerical simulation study and sensitivity analysis become essential to investigate the effects of main operational parameters and evaluate the performance of the integrated CO2 Huff-n-Puff and WAG process in low-pressure heterogeneous reservoir to achieve the maximum benefits. According to simulation results, …
Evaluation Of Captured Co2 And Waste H2 As Potential Feedstock For Methanol Production, Kankanit Kitsahawong
Evaluation Of Captured Co2 And Waste H2 As Potential Feedstock For Methanol Production, Kankanit Kitsahawong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Global warming is the critical issue that is the result of Greenhouse Gases (GHGs) emission. Carbon dioxide (CO2) is concerned to be major GHGs. Thus, Carbon dioxide utilization is the promising pathway to reduce the emission of CO2. To utilize CO2, waste hydrogen from sodium methoxide production is used to produce methanol which can be recycled as reactant of sodium methoxide synthesis. Carbon dioxide hydrogenation process is used for produce methanol from CO2 and waste H2 from various size of sodium methoxide production process. In every size of methanol production process, methanol which produce from the process is 16.3% of …
Zeolitic Imidazolate Framework (Zif) Incorporated Membrane For Co2/Ch4 Separation, Nampetch Padungpetch
Zeolitic Imidazolate Framework (Zif) Incorporated Membrane For Co2/Ch4 Separation, Nampetch Padungpetch
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biogas is the alternative energy that has a methane gas as the main composition. Before using it, biogas must be upgraded by the removal of all impurities especially CO2. The membrane technology is considered an efficient and environmentally friendly process for biogas upgrading. However, there is still a limited number of promising membranes. Accordingly, this study aims to develop the hollow fiber membrane for the biogas upgrading. The synthesized hollow fiber membranes, which were a composite membrane, were composed of a support layer of polyetherimide (PEI) and a mixed matrix selective layer of commercial poly(ether-block-amide) (Pebax 1657) and zeolitic imidazolate …
Catalytic Activity Of Cu-Ceo2zro2 For Biodiesel Production, Wasupon Wongvitvichot
Catalytic Activity Of Cu-Ceo2zro2 For Biodiesel Production, Wasupon Wongvitvichot
Chulalongkorn University Theses and Dissertations (Chula ETD)
CeO2-ZrO2 was synthesized by co-precipitation (CZ copre) and nanocasting (MSP CZ) methods for supporting 9%wt Cu catalyst loaded by deposition-precipitation (DP) method (CuCZ copre and Cu-MSP CZ, respectively). Both CuCZ copre and Cu-MSP CZ were used in esterification reaction for biodiesel production. Structure and specific surface area of the synthesized supports and catalysts were characterized by XRD and BET tecnhiques. It was found that the specific surface area of CZ copre was less than MSP CZ support. The XRD result of CuCZ copre exhibited the diffraction peak of CuO, indicating the agglomeration of Cu species on support while that of …
Designing Efficient Petroleum Fiscal System For Mozambique, Nelson Victor
Designing Efficient Petroleum Fiscal System For Mozambique, Nelson Victor
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, tax regime is designed to attract investment and provide the contractor with fair return on investment, at the same time, provide the host government with adequate resources for rent, thereby resulting in win-win situation. This study analyses the existing petroleum fiscal regime in the Republic of Mozambique and proposes a more efficient and flexible regime. The analysis shows that the government take currently remains at around 39% while the contactors' net present value (NPV) increases as field sizes and oil prices increase. The current system is considered a regressive system which is inefficient in distributing wealth from oil profit. …
Carbon Nanotube/Polymer Composite Membrane For Co2 Capture, Pacharaporn Yaisanga
Carbon Nanotube/Polymer Composite Membrane For Co2 Capture, Pacharaporn Yaisanga
Chulalongkorn University Theses and Dissertations (Chula ETD)
Membrane gas absorption (MGA) was applied for carbon dioxide capture due to its unique potential, such as independent adjustment of gas and liquid, compact equipment installation, and sizable module. However, a major issue of MGA is membrane wetting, causing lower absorption efficiency and membrane damages. Hydrophobicity is one of the key parameters to improve membrane property for solving such problem. This thesis focused on using carbon nanotubes as the filler to composite with polyacrylonitrile (PAN) or polyvinylidene fluoride (PDVF) via a phase inversion technique to improve membranes hydrophobicity. In case of PAN, the results showed that the addition of CNT …
Novel Shape Memory Polymer From Bio-Based Polybenzoxazine/Bio-Based Epoxy Copolymers, Phakakrong Hombunma
Novel Shape Memory Polymer From Bio-Based Polybenzoxazine/Bio-Based Epoxy Copolymers, Phakakrong Hombunma
Chulalongkorn University Theses and Dissertations (Chula ETD)
Shape memory polymers (SMPs) are known as smart polymer materials which can be deformed and fixed in a temporary shape and can recover to its original shape upon an external stimulus such as temperature which is the main stimulus for general SMPs. In this research, a renewable natural resource based on vanillin-furfurylamine benzoxazine (V-fa) and eugenol-furfurylamine benzoxazine (E-fa) are developed to substitute the use of petroleum based polybenzoxazine. The as-synthesized V-fa and E-fa show the degradation temperature at 5% weight loss to be as high as 343 and 310°C and char content to be 66 and 54%, respectively. Effects of …
Effects Of Fillers On The Properties Of Polypropylene For Fused Deposition Modeling-Based 3d Printing Technique, Chomphoonut Buaprommee
Effects Of Fillers On The Properties Of Polypropylene For Fused Deposition Modeling-Based 3d Printing Technique, Chomphoonut Buaprommee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The objective of this research was to study the influence of filler contents and filler types on the tensile properties and shrinkage behavior of polypropylene composites to develop the properties of polypropylene (PP) to be a raw material for fused deposition modeling (FDM) technique. PP was compounded with three fillers, i.e., talc and milled glass fiber with aspect ratio 5.4 and 15.4, at various contents of 10, 20 and 30 wt%. The test specimens were fabricated by FDM and injection molding techniques for tensile and shrinkage tests. The findings showed that the increase of filler contents into PP matrix tended …
Microwave Heating With Potassium Hydroxide Activation For Converting Water Hyacinth Into Activated Carbon, Purichaya Kuptajit
Microwave Heating With Potassium Hydroxide Activation For Converting Water Hyacinth Into Activated Carbon, Purichaya Kuptajit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Activated carbon was successfully synthesized form dried water hyacinth via KOH activation with microwave irradiation. Resultant activated carbon with large specific surface area can be produced using microwave irradiation for 1 minute which was consumed less time than conventional heating method that consumed 1 hour. Microwave irradiation can be a strategic way to improve uniform and quick heating to prepare porous carbons by inducing dipole rotation in atomic scale and creating a frictional force between atoms and molecules within heated material so that volumetric heating inside the heated material is realized. The BET analysis shown that the activated carbon, derived …
Mechanism And Performance Of Solid Non-Particulate Soil (Waxy Solid) Removal From Fabrics, Jarussri Chanwattanakit
Mechanism And Performance Of Solid Non-Particulate Soil (Waxy Solid) Removal From Fabrics, Jarussri Chanwattanakit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Methyl palmitate or palmictic acid methyl ester was used as both a model solid fat and an oily soil was removed from cotton and polyester above and below the melting point. Surfactants studied were extended surfactants (C12,13-4PO-SO4Na , C12,14-10PO-2EO-SO4Na and C12,14-16PO-2EO-SO4Na), alcohol ethoxylate (EO9), sodium dodecyl sulfate (SDS), methyl ester sulfonate (MES), methyl ester ethoxylate (MEE), and mixed surfactants between extended surfactant (C12,13-4PO-SO4Na) and sodium mono- and dimethyl naphthalene sulfonate (SMDNS). Above the melting point (~30 ºC) of methyl palmitate, the maximum oily soil removal was found to correlate well with the lowest dynamic interfacial tension (IFT) with increasing washing …
Use Of Anionic Surfactant In Regeneration Of Spent Activated Carbon, Buch Kallapadee
Use Of Anionic Surfactant In Regeneration Of Spent Activated Carbon, Buch Kallapadee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Surfactant-enhanced carbon regeneration (SECR) is a regeneration process that utilizes surfactant solution to dissolve adsorbed organic from spent activated carbon. Sodium dodecyl sulfate (SDS) and methyl ester sulfonate (MES) are anionic surfactants that are used in this investigation. The study is done in 3 steps: sample characterization, regeneration and water flushing step. The proximate analysis of spent activate carbon contains 27.5% moisture, 27.2% volatile matter content, 10% total ash content. The spent activated carbon also contains 18.4% benzene. In regeneration step, the benzene removal by SDS and MES solution were compared. The effect of concentration, solution flow rate and temperature …
Conversion Of Palm Fatty Acid Distillate To Biojet Fuel Over Ni/Hy-Pditioz Core-Shell Catalyst, Chanakran Homla-Or
Conversion Of Palm Fatty Acid Distillate To Biojet Fuel Over Ni/Hy-Pditioz Core-Shell Catalyst, Chanakran Homla-Or
Chulalongkorn University Theses and Dissertations (Chula ETD)
Generally, jet fuel is obtained from the refining of petroleum feedstock in order to powering the aircrafts, hence the world is more confronting a problem with increasing air pollution emission. Therefore, biojet fuel is introduced as an alternative way to solve the problem. Biojet fuel can be derived from bio-based feedstock such as palm fatty acid distillate or PFAD. Which is converted via the deoxygenation reaction in order to remove oxygenated compounds, carboxylic and carbonyl groups in the fatty acid molecules then followed by hydrocracking and hydroisomerization reaction. The heterogeneous catalyst is used to convert PFAD into saturated paraffins in …
Analysis Of Biomarkers In Crude Oils, Processed Oils, And Spilled Oils, Pornpetch Hattakijvilai
Analysis Of Biomarkers In Crude Oils, Processed Oils, And Spilled Oils, Pornpetch Hattakijvilai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Oil spills in marine are commonly come from crude oils, fuel oils and lubricating oils by accidental leakages or purposeful discharges to the surroundings. As crude oil and fuel oil which refined from the heavy fraction of crude oil have similar physical properties especially if they were weathering, it is difficult to differentiate that the spill has the origin from crude oil or fuel oil. In this study, five crude oils, two fuel oils, one fresh and one used lube oil that are typically used in Thailand were investigated. All crude oils, fuel oils, and used lube oil were weathered …
ปฏิกิริยาทรานส์เอสเทอริฟิเคชันของกลีเซอรอลและไดเมทิลคาร์บอเนตโดยใช้ตัวเร่งปฏิกิริยาโซเดียมฟอสเฟต, แพรพรรณ ศรีสอ้าน
ปฏิกิริยาทรานส์เอสเทอริฟิเคชันของกลีเซอรอลและไดเมทิลคาร์บอเนตโดยใช้ตัวเร่งปฏิกิริยาโซเดียมฟอสเฟต, แพรพรรณ ศรีสอ้าน
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้เป็นการศึกษาปฏิกิริยาทรานส์เอสเทอริฟิเคชันของกลีเซอรอลและไดเมทิลคาร์บอเนต โดยใช้ตัวเร่งปฏิกิริยาโซเดียมฟอสเฟต โดยทำการทดลองในเครื่องปฏิกรณ์แบบกะ ปริมาณตัวเร่งปฏิกิริยาโซเดียมฟอสเฟตร้อยละ 1 3 และ 5 โดยน้ำหนักของกลีเซอรอล อัตราส่วนโดยโมลระหว่างกลีเซอรอลต่อไดเมทิลคาร์บอเนต 1:1 1:2 1:3 และ 1:4 อุณหภูมิในการทำปฏิกิริยาที่ 60 70 75 และ 80 องศาเซลเซียส ผลการทดลองแสดงให้เห็นว่า ตัวเร่งปฏิกิริยาโซเดียมฟอสเฟตมีความว่องไวในการทำปฏิกิริยาทรานส์เอสเทอริฟิเคชันของกลีเซอรอลและไดเมทิลคาร์บอเนต การเพิ่มปริมาณของตัวเร่งปฏิกิริยาที่ไม่เกินร้อยละ 3 โดยน้ำหนักของกลีเซอรอล ส่งผลให้ค่าร้อยละผลได้ของกลีเซอรอลคาร์บอเนตมีค่าเพิ่มมากขึ้น การลดลงของอัตราส่วนโดยโมลระหว่างกลีเซอรอลต่อไดเมทิลคาร์บอเนต ส่งผลให้ค่าร้อยละการแปลงผันของกลีเซอรอลและค่าร้อยละผลได้ของกลีเซอรอลคาร์บอเนตเพิ่มมากขึ้น นอกจากนี้ยังช่วยลดการเกิดดีคาร์บอกซิเลชันของกลีเซอรอลคาร์บอเนตไปเป็นไกลซิดอลอีกด้วย ในส่วนของการเพิ่มอุณหภูมิในการทำปฏิกิริยาส่งผลให้ค่าร้อยละการแปลงผันของกลีเซอรอล ค่าร้อยละผลได้ของกลีเซอรอลคาร์บอเนตเพิ่มสูงขึ้นและยังช่วยให้ปฏิกิริยาเข้าสู่สมดุลเร็วมากยิ่งขึ้น
Effects Of Ratio Of Oxygen Partial Pressure To Propane Partial Pressure And Temperature On Non-Faradaic Electrochemical Modification Of Catalytic Activity (Nemca) Of Propane Oxidation On Pt-Ysz, Sareerat Thongsrigate
Effects Of Ratio Of Oxygen Partial Pressure To Propane Partial Pressure And Temperature On Non-Faradaic Electrochemical Modification Of Catalytic Activity (Nemca) Of Propane Oxidation On Pt-Ysz, Sareerat Thongsrigate
Chulalongkorn University Theses and Dissertations (Chula ETD)
The effects of electrochemical promotion of catalysis (EPOC) or non-faradaic electrochemical modification of catalytic activity (NEMCA) of sputtered-Pt catalyst on Y2O3-stabilized-ZrO2 (YSZ) disk, an O2- conductor, were studied with the catalytic reaction of propane oxidation, which was chosen to model the combustion of residual hydrocarbons in catalytic converters. In electrochemical promotion, the catalyst was electrochemically promoted by applying electric current or potential between the Pt and Au electrodes of YSZ disk. Catalytic performances were studied under the ratio of oxygen partial pressure to propane partial pressure difference of 1 to 5 and partial pressure of propane was 1 kPa, in …
Synthesis And Characterization Of Cross-Linked Polyimide Film Using Tolylene Diisocyanate, Sirichai Reeyakad
Synthesis And Characterization Of Cross-Linked Polyimide Film Using Tolylene Diisocyanate, Sirichai Reeyakad
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cross-linked polyimide films were synthesized by the reaction between diisocyanate groups and hydroxyl functional groups in polyimide structure, which was confirmed by IR. During the thermal treatment of the cross-linked polyimide, the thermal labile component (CO₂) in the urethane segments was decomposed which might generate pores in the film. The presence of the pores was confirmed from the dielectric constant of the film. The dielectric constant of the films decreased with the increase of TDI loading. By comparing the properties of the films, the PI50-C1.0 exhibited optimum mechanical and good dielectric properties. The cross-linked structure was also confirmed by DMA. …
Catalytic Ethanol Dehydration To Diethyl Ether Over Palladium-Modified Phosphorus Gamma Alumina Catalysts, Chakkrit Khaochartchai
Catalytic Ethanol Dehydration To Diethyl Ether Over Palladium-Modified Phosphorus Gamma Alumina Catalysts, Chakkrit Khaochartchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
The gamma alumina (γ-Al2O3) catalyst was modified with phosphorous (P) by acid activation technique and palladium (Pd) by the incipient wetness impregnation technique. The obtained catalysts were characterized with various techniques including X-ray diffraction (XRD), inductively coupled plasma (ICP), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX), N2 physisorption, ammonia temperature-programmed desorption (NH3-TPD), and thermogravimetric analysis (TGA). In addition, these modified catalysts were tested in ethanol dehydration reaction in a fixed-bed microreactor to determine ethanol conversion and product yield at the atmospheric pressure with temperatures ranging from 200-400oC. From the results, the phosphorous modification diminished the amount of …
Co2 Methanation Over Nial2o4 Spinel - Based Catalysts, Chanya Thamma
Co2 Methanation Over Nial2o4 Spinel - Based Catalysts, Chanya Thamma
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the present work, a series of NiO/NiAl2O4 catalysts were prepared by co-precipitation method with molar ratio of Ni/Al equal 1/2 at different precipitation temperatures (30 and 80oC) and calcination temperatures (500, 700, 900, and 1200oC). The catalyst properties were characterized by using N2 physisorption, X-ray diffraction, H2 - TPR, SEM, and TEM. The NiO/NiAl2O4 precipitated at 80oC and calcined at 900oC showed the best activity in CO2 methanation at 350oC with conversion 92% and 100% methane selectivity without CO formation. The optimal of NiO and NiAl2O4 composition at 24.7% and 75.3%wt could provide a stabilizing effect preventing the metal …
Dehydration And Oxidative Dehydrogenation Of Ethanol Over Sba-15 Based Catalysts Prepared By Sol-Gel And Hydrothermal Methods, Chaowat Autthanit
Dehydration And Oxidative Dehydrogenation Of Ethanol Over Sba-15 Based Catalysts Prepared By Sol-Gel And Hydrothermal Methods, Chaowat Autthanit
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this present study, characteristics and catalytic properties of zirconium (Zr) and bimetal (Zr and La) containing in SBA-15 catalysts and different VOx/SBA-15 catalysts were determined and well related. The study was divided into three parts. Regarding to the first part, zirconium (Zr) and bimetal (Zr and La) containing in SBA-15 synthesized by sol-gel and hydrothermal methods were compared. The results showed that the incorporation of Zr and bimetal (Zr and La) had an effect on the textural properties of both synthesized SBA-15 catalysts. Surface acidity in the SBA-15 suggests new active sites, especially Brønsted acid type. In the second …
Functionalization Of Carbon Nanohorns And Their Catalysis Applications, Chompoopitch Termvidchakorn
Functionalization Of Carbon Nanohorns And Their Catalysis Applications, Chompoopitch Termvidchakorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Carbon nanohorns (CNHs) synthesized by gas-injected arc-in-water method were functionalized in this study. Metal (Ni, Cu, Fe, Pd, and Pt) and their alloy (NiCu, NiFe, NiPd, and NiPt) hybridized with CNHs were successfully produced. In addition, thermal and acid treatment was applied on the hybridized materials. Effect of metal loading and functionalizing conditions on characteristics of CNHs and functionalized CNHs was examined based on transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), N2 sorption, Raman spectroscopy, Fourier transform infrared (FT-IR) spectrometer, temperature programmed desorption of ammonia (NH3-TPD) analysis. The functionalized CNHs were applied as a catalyst in …
Conversion Of Glucose To Levulinic Acid By Fe/Carbon Nanoparticle Catalyst Synthesized From Lubricant Oil And Ferrocene, Jirarat Kaewngam
Conversion Of Glucose To Levulinic Acid By Fe/Carbon Nanoparticle Catalyst Synthesized From Lubricant Oil And Ferrocene, Jirarat Kaewngam
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, production of levulinic acid which is one of promising chemical substances derived from biomass has been intensively investigated. Different catalyst types have been employed to produce levulinic acid from glucose including zeolite, metal phosphate and alumina. However, carbon based catalysts with high thermal stability, ease of surface functionalization and acid-base resistance were not widely studied. In this thesis, carbon nanoparticles synthesized from lubricant oil and ferrocene via co-pyrolysis was fully studied for glucose conversion to levulinic acid. The effect of carbon nanoparticles acid treatment was mainly investigated in terms of glucose conversion and levulinic acid yield. Pristine magnetic carbon …
Effects Of Carbon Fiber And Glass Fiber On Shape Memory Polymers Based On Benzoxazine-Epoxy Binary Systems, Jutamart Plylaharn
Effects Of Carbon Fiber And Glass Fiber On Shape Memory Polymers Based On Benzoxazine-Epoxy Binary Systems, Jutamart Plylaharn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Recovery stress is an important parameter of shape memory polymers. Generally, recovery stress in SMPs can be enhanced by using fiber reinforced composites with suitable reinforcing agents such as carbon fiber or glass fiber. We aim to study effects of carbon fiber and glass fiber on thermal, mechanical, and shape memory properties of benzoxazine-epoxy SMPs, particularly on recovery stress enhancement. The compositions of carbon fiber and glass fiber reinforced benzoxazine-epoxy SMPs were in a range of 30 to 50vol%. The carbon fiber and glass fiber reinforced benzoxazine-epoxy shape memory polymer was compression-molded at 170oC under a pressure of 10 MPa …
Photocatalytic Degradation Of Methylene Blue Over Polydopamine-Ag/Tio2, Kamonthip Tammarakwattana
Photocatalytic Degradation Of Methylene Blue Over Polydopamine-Ag/Tio2, Kamonthip Tammarakwattana
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the effect of silver and polydopamine (PDA) doping on TiO2 catalysts for the photocatalytic degradation of methylene blue in aqueous phase. Titanium dioxide was synthesized via a sol-gel method and was calcined at 400 °C for two hours. Silver was loaded onto TiO2 by an incipient wetness impregnation method. The amount of Ag was varied from 0.5%wt to 3%wt. Then polydopamine-Ag/TiO2 catalyst was prepared by an impregnation method, using dopamine as a precursor. The amounts of polydopamine were 5%wt and 10%wt. All catalysts were characterized by N2 physisorption, ICP-OES, XRD, FTIR, CO chemisorption, Photoluminescence, and UV-Visible spectrophotometry. …
Performance Comparison Of Different Membrane Micro-Channel Reactors For Methanol Production From Biogas And Hydrogen, Khunnawat Ountaksinkul
Performance Comparison Of Different Membrane Micro-Channel Reactors For Methanol Production From Biogas And Hydrogen, Khunnawat Ountaksinkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In order to integrate simultaneous methanol production with biogas upgrading in a single unit, the computational fluid dynamics (CFD) models of a triple pipe tubular membrane reactor (TMR) and a planar membrane micro-structured reactor (MMR) were established via COMSOL Multiphysics 5.3a and compared their effect on reactor performance under predetermined condition. For the conceptual design of these reactors, the channel inside the reactors can be divided into three parts; biogas channel (BC), reaction channel (RC) and sweep gas channel (SC). The CO2 in biogas entering into BC is separated through CO2 selective membrane to produce methanol inside RC. Afterwards, water …
Computational Fluid Dynamic Study Of Sorption Enhanced Steam Reforming Of Methane/Ethanol In Circulating Fluidized Bed System, Kiattikhoon Phuakpunk
Computational Fluid Dynamic Study Of Sorption Enhanced Steam Reforming Of Methane/Ethanol In Circulating Fluidized Bed System, Kiattikhoon Phuakpunk
Chulalongkorn University Theses and Dissertations (Chula ETD)
Two-dimensional fluid dynamic models were used to optimize and design a proper pilot-scale system for sorption enhanced steam methane reforming (SESMR) and sorption enhanced steam reforming of ethanol (SESRE) in a circulating fluidized bed reactor (CFBR) using Ni-based catalyst and dolomite as sorbent. The CFBR system was separately designed as 3 parts: including a SESMR riser, a SESRE and a regenerator. The SESMR riser could get H2 purity reached equilibrium of 98.58% in dry basis with the highest H2 flux of 0.301 kg/m2s when operating with steam to carbon ratio of 4 mol/mol, gas velocity of 6 m/s, inlet temperature …
Synthesis Of Ptco/Tio2 Catalysts By Flame Spray Pyrolysis For Selectiive Hydrogenation Of Furfural To Furfuryl Alcohol, Kitima Kruachao
Synthesis Of Ptco/Tio2 Catalysts By Flame Spray Pyrolysis For Selectiive Hydrogenation Of Furfural To Furfuryl Alcohol, Kitima Kruachao
Chulalongkorn University Theses and Dissertations (Chula ETD)
The selective hydrogenation of furfural to furfuryl alcohol (FA) was carried out in a batch reactor at 50 ̊C and 20 bar H2 using Pt-Co/TiO2 with 0.5 wt%Pt and 0-0.8 wt%Co. The catalysts were characterized by X-ray diffraction (XRD), N2-physisorption, X-ray photoelectron spectroscopy (XPS), H2-temperature programmed reduction (H2-TPR), atomic absorption spectroscopy (AAS), CO-pulse chemisorption and transmission electron microscopy (TEM). Addition of Co into monometallic (I) Pt/TiO2 catalyst increased both furfural conversion and FA selectivity because it prevented anatase to rutile transformation of TiO2 and increased the interaction between metal and TiO2. However, Co adding into monometallic (F) Pt/TiO2 catalyst resulted …
Effects Of Polyol Molecular Weights On Thermally Reversible Light Scattering Behaviors Of Benzoxazine-Urethane Copolymers, Kittipon Bunyanuwat
Effects Of Polyol Molecular Weights On Thermally Reversible Light Scattering Behaviors Of Benzoxazine-Urethane Copolymers, Kittipon Bunyanuwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The thermally reversible light scattering behaviors of benzoxazine-urethane copolymer was investigated in this work. Benzoxazine monomers (BA-a) were synthesized by the solventless synthesis technique from bisphenol-A, para-formaldehyde, and aniline with the molar ratio of 1:4:2, respectively. Urethane prepolymer was prepared by reacting poly(propylene glycol) (Mw = 1000, 2000, or 3000 g/mol) with toluene diisocyanate (TDI) at the molar ratio of 1:2 under a nitrogen atmosphere. The obtained urethane prepolymer (PU) was labelled as PU1K, PU2K, and PU3K with respect to the molecular weights of polyether polyol employed in the preparation step. Urethane prepolymer and benzoxazine monomers were crosslinked during the …