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Full-Text Articles in Engineering
Characteristics And Catalytic Properties Of Copper On Mcf-Si And Sba-15 For Hydrogenation Of Carbon Dioxide, Sirimas Suelueam
Characteristics And Catalytic Properties Of Copper On Mcf-Si And Sba-15 For Hydrogenation Of Carbon Dioxide, Sirimas Suelueam
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, the production of methanol from the hydrogenation of carbon dioxide is widespread. The current popular catalysts include copper oxide, zinc oxide and aluminum oxide (CZA) catalysts. As the reaction progresses, the catalyst forms coke. This causes the efficiency of the catalyst to decrease. In this study, the copper catalyst on the mesoporus silica support was investigated. This type of support has high thermal stability. Cu catalysts were synthesized on MCF-Si and SBA-15 supports with different pore morphology such as spherical and hexagonal shape, respectively, by wetness impregnation (W) method and incipient wetness impregnation (IW) with a copper loading …
Comparison Of Techno-Economic Analysis Of 1,3-Propanediol Production From Crude Glycerol Via Chemical And Biological Methods, Sivatchaya Boriboon
Comparison Of Techno-Economic Analysis Of 1,3-Propanediol Production From Crude Glycerol Via Chemical And Biological Methods, Sivatchaya Boriboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, the biodiesel industry is expanding rapidly which could lead to an oversupply of the by-product, crude glycerol. To manage this, crude glycerol should be converted into value-added chemicals such as 1,3-propanediol (1,3-PDO). In this study, the production of 1,3-PDO via catalytic reaction is simulated using a process simulator to evaluate its techno-economic performance as well as its environmental impact. The obtained results will be compared with the conventional production of 1,3-PDO to point out the advantages that the catalytic reaction can offer in terms of economic, energy utilization, raw material utilization, and environmental impacts.
Effects Of Zinc Oxide On Thermal, Mechanical, Morphological, And Gas Barrier Properties Of Polybutylene Succinate/ Poly(3-Hydroxybutyrate-Co-4-Hydroxybutyrate) Films, Sunisa Suwatthi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, conventional polymers from petrochemical processes have low biodegradability and remain in the environment for several hundred years. This has negative effects on the environment. This research aims to improve the properties of biopolymers such as poly(butylene succinate) (PBS) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB). P3HB4HB was selected to blend with PBS in with weight ratios of PBS:P3HB4HB was 90/10 and ZnO nanoparticles (0.5, 1 and 2%) was selected as a nucleating agent. The melt blending process using an internal mixer and molded into a film using a compression molding process. The chemical structures, morphological properties, thermal properties, dynamic mechanical properties, mechanical properties …
The Study Of Weave-Pattern Effect On Filtration Performance Of Woven Filter Cloths By Computational Fluid Dynamic Modeling, Wisit Bandasak
The Study Of Weave-Pattern Effect On Filtration Performance Of Woven Filter Cloths By Computational Fluid Dynamic Modeling, Wisit Bandasak
Chulalongkorn University Theses and Dissertations (Chula ETD)
An important global problem that has an impact on both human health and the environment is air pollution. Exercise and outdoor activities are essential for human well-being, but they can also have a detrimental effect on health and the environment. For example, PM2.5 and PM10 particles can enter the lungs and cause respiratory and cardiovascular disorders. Moreover, masks must be worn in order to stop the COVID-19 epidemic from spreading. Nevertheless, not all masks are effective in preventing viruses and air pollution. Consequently, selecting the proper mask is essential for avoiding health risks. Using the use of computational fluid dynamics, …
Design Of Process For Recovery Of Gold And Nickel Ions From Wastewater Of Metal Plating Process In Electronics Industry Using Hollow Fiber Supported Liquid Membrane, Wanchalerm Srirachat
Design Of Process For Recovery Of Gold And Nickel Ions From Wastewater Of Metal Plating Process In Electronics Industry Using Hollow Fiber Supported Liquid Membrane, Wanchalerm Srirachat
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the manufacture of printed circuit boards (PCBs), electroless nickel immersion gold (ENIG) plating is widely applied. During the plating process, excess nickel and gold plating solutions, which adheres to the workpiece, is removed. As a result, economical quantities of nickel and gold ions accumulate in the rinse water baths and can then be collected. In this work, the simultaneously selective extraction and recovery of nickel and gold ions using a single-step operation of hollow fiber supported liquid membrane (HFSLM) technique was studied. Real rinse wastewater from the plating process containing trace nickel ions (Ni(II)) of 15 mg/L and gold …
Control Of A Polybutylene Succinate (Pbs) Polymerization In A Semi-Batch Reactor By Neural Network Model Based Predictive Controller, Takorn Plengsangsri
Control Of A Polybutylene Succinate (Pbs) Polymerization In A Semi-Batch Reactor By Neural Network Model Based Predictive Controller, Takorn Plengsangsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polybutylene succinate (PBS) is a biodegradable plastic known for its strength and versatility in various applications. This research presents a data-driven approach to simulate temperature control in a semi-batch reactor during polymerization, the performance of the proposed approaches was compared against conventional controllers, including PID control and first-principles model MPC control. The study developed neural network model-based predictive control (NNMPC) and multiple neural network model-based predictive control (Multi-NNMPC), using Python and Tensorflow. Neural network models were trained by using a wide range of dynamic data with varying numbers of neurons in hidden layers to investigate the process dynamics under different …
Effect Of Salinity Contrast Between Formation Water And Injected Low Salinity Water On Low Salinity Waterflooding In Shaly-Sandstone Formation, Sarun Phuenghansaporn
Effect Of Salinity Contrast Between Formation Water And Injected Low Salinity Water On Low Salinity Waterflooding In Shaly-Sandstone Formation, Sarun Phuenghansaporn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Low salinity waterflooding is an improving oil recovery technique that is highly mentioned nowadays as it is cost-efficient and environmentally friendly. The technique involves injecting water with lower salinity compared to formation salinity to shift the surface equilibrium toward the liberation of oil from the rock surface. Nevertheless, successful of this technique depends on many parameters especially the presence of clays. Several types of clays can be found in oil reservoirs, and they may react to different cations in inject low salinity in different ways, resulting in different magnitudes of oil recovery. Moreover, the contrast of salinity between formation water …
The Study Of Oxygenated Compounds For Oil Fingerprinting Application, Khairunisa Betariani
The Study Of Oxygenated Compounds For Oil Fingerprinting Application, Khairunisa Betariani
Chulalongkorn University Theses and Dissertations (Chula ETD)
Oil spills have a large impact on the marine and coastal environments. The characterization of petroleum or its products spilled in the environment to its source rocks is an important tool to assist in the resolution of issues of environmental impact and legal responsibility. The composition and physical properties of spilled oils have changed during the weathering process. Petroleum biomarkers is a tool for defining the origin of each oil, which is unique for each type of oil. In general, petroleum biomarkers (i.e., hopane group) are widely used for oil fingerprinting by following the NORDTEST methodology. Besides the hopane group, …
Economic Evaluation Of Ethyl Lactate Production Via Reactive Distillation At Different Concentrations Of Lactic Acid, Nattapat Klin-U-Bol
Economic Evaluation Of Ethyl Lactate Production Via Reactive Distillation At Different Concentrations Of Lactic Acid, Nattapat Klin-U-Bol
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ethyl lactate is a green solvent made from agricultural crops, making it more environmentally friendly than petrochemical solvents. The product is obtained via esterification of lactic acid with ethanol over Amberlyst-15 acid catalyst in a reactive distillation column. In commercial-scale production of ethyl lactate, this work designs production processes at two concentrations of lactic acid (50 and 85 wt.%) and two ethanol feed temperatures (25 and 85 °C). Highly concentrated lactic acid can result in adverse effects, such as increased oligomers and reduced desired products, making a comprehensive simulation of the production process necessary to evaluate energy consumption, economics, and …
Optimization Of Blast Design For Better Fragmentation & Reduction Of Ground Vibration At Khao Mai Nuan Pyrophyllite Mine, Saraburi Province, Thailand, Arif Khan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Control blasting with better fragmentation is very important to decrease the environmental impacts of blasting and the cost of downstream mining operations such as loading, transportation, crushing, and milling. Proper blasting designs with optimized parameters such as burden, spacing, stemming, sub-drilling, and amount of explosive ensure the required fragmentation with ground vibration within the standards set by different monitoring agencies. This study dealt with the blasting design parameters, fragmentation, and ground vibration at the Khao Mai Nuan Pyrophyllite quarry Saraburi province, Thailand. First, grab samples were collected from the quarry's active benches and tested in a lab for strength, compositions …
Scale Up Of Benzoxazinone Derivative Synthesis In Batch Reactor, Sumate Boonkird
Scale Up Of Benzoxazinone Derivative Synthesis In Batch Reactor, Sumate Boonkird
Chulalongkorn University Theses and Dissertations (Chula ETD)
Benzoxazinone derivative is one of starting materials in the synthesis of Deferasirox (a Chelating iron for thalassemia patient). The parameters of Benzoxazinone derivative synthesis were investigated from the condensation of salicylic acid, salicylamide, cyanuric chloride, and triethylamine using toluene as solvent. The mole equivalent ratio of salicylic acid: salicylamide:cyanuric chloride:triethylamine at 1:1:0.67:1 provided the 46.77% yield of Benzoxazinone derivative in laboratory scale. Surprisingly, 4-chloro-2-(2-hydroxyphenyl)-4H-benzo[e][1,3]oxazine-4-ol was observed in the synthesis of Benzoxazinone derivative. In addition, the reaction scheme of Benzoxazinone derivative synthesis was proposed as a model for the study of the chemical kinetic constant. Furthermore, the scale up of Benzoxaxinone …
Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad
Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study proposes an alternative approach to address global warming concerns by introducing bio-based succinic acid production derived from molasses and waste CO2 in ethanol production as a substitute for conventional petroleum-based methods. The evaluation focuses on the downstream process; reactive extraction, aiming to assess its feasibility in terms of technical, economic, energy, and CO2 emission performance. The results indicate that the integrated process, Int. ETOH+SA 25:75, exhibits remarkable benefits, including a 66% reduction in CO2 emissions from ethanol production, a 77% decrease in energy consumption compared to petroleum-based methods, and NPV of 2,180 million USD with a 40.81% IRR …
Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong
Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lanthanum doped strontium titanate (LST) is a perovskite cathode in Solid Oxide Electrolysis Cell (SOEC) which shows great performance in syngas production from CO2 and steam feed. However, the LST type cathode suffers from structural stability. Sulfur containing in industrial exhaust gas can affect its durability which inhibit the technology in real application. Therefore, to improve sulfur tolerance, La0.3Sr0.7Ti1-yCoyO3-δ (LSTC) by adding Co2+ metal ion at B-site when y is 0 to 20%mol was synthesized. Citrate acid-nitrate combustion method was used and the synthesized powder. LST and La0.3Sr0.7Ti0.9Co0.10O3-δ (LSTC0.10) exhibited single phase perovskite while La2O3 and La(OH)3 were observed in …
Synthesis Of Zinc Sulfide Nanoparticles Using Microemulsion Generated By Hydrodynamic Cavitation Method, Nachapa Choojan
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, …
Effects Of Types Of Arylamine Based Benzoxazine Binders In Brake Pads On Thermal Degradation Kinetics, Juntasak Wangrangsimakul
Effects Of Types Of Arylamine Based Benzoxazine Binders In Brake Pads On Thermal Degradation Kinetics, Juntasak Wangrangsimakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to investigate the effect of the alkyl-substituted aromatic amines of polybenzoxazine resins used as binders in the non-asbestos friction composite materials on their thermal degradation and stability. The effects of BA-35x polybenzoxazine resin used as a binder of the brake pad were investigated using thermogravimetric analysis (TGA) under nitrogen atmosphere at various heating rates of 1, 5, 10, 20 and 25 °C/min by applying the model of Advanced iso-conversional method. For the friction composite system using BA-35x as binder, the derivative thermogram exhibited six stages of thermal decomposition reaction. The activation energies of six stages were determined …
Synthesis Of Molybdenum-Based Catalysts On Carbon Support For Partial Hydrogenation Reaction Of Biodiesel, Dolrudee Jaruwat
Synthesis Of Molybdenum-Based Catalysts On Carbon Support For Partial Hydrogenation Reaction Of Biodiesel, Dolrudee Jaruwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, biodiesel is a renewable energy, which can decrease fossil fuel. It helped reducing air pollution. Partial Hydrogenation is one process which improves the biodiesel quality. In this research, activated carbon was produced from cattail leave via hydrothermal carbonization and chemical activation. The activated carbon was treated with 4 M of potassium hydroxide at 900oC, which exhibits 1323.38 m2g-1 of SBET. Several type of catalysts (Mo, Ni, Ci, Fe, MoNi, MoCu, and MoFe) were studied in this research, which were prepared using a rotary evaporation technique. The experiments reveal that MoNi/C catalyst indicate the highest dispersion of metal particle. The …
Electroless Cunisn Electrocatalyst Supported On Carbon Fabric For Electrochemical Reduction Of Co2, Atikom Hongmeuan
Electroless Cunisn Electrocatalyst Supported On Carbon Fabric For Electrochemical Reduction Of Co2, Atikom Hongmeuan
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the present work, tri-metallic alloy electrocatalysts containing copper (Cu), nickel (Ni), and tin (Sn) supported on Pd-catalyzed carbon fabric substrate were prepared through a simple electroless deposition method. As-deposited Cu-Ni-Sn electrocatalyst was employed in the CO2-ERR in an H-cell type reactor. For the effect of electroless deposition time (15, 30 and 45 mins) on tri-metallic alloy electrocatalyst, the result showed that there is no significant difference for all samples based on the XRD pattern, indicating the deposition time had no effect on the crystalline structure of all catalyst. In addition, the evaluation of the ability of the CO2-ERR on …
Prediction Of Coke Formation Over A Catalyst Particle For Dry Reforming Of Methane, Chananun Rojanarungruengporn
Prediction Of Coke Formation Over A Catalyst Particle For Dry Reforming Of Methane, Chananun Rojanarungruengporn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, global warming is a significant environmental problem causing various impacts across the globe. Dry reforming of methane (DRM) is one of the reactions that can utilize CO2 effectively. However, the major problem of DRM process is the deactivation of catalysts caused by coke formation over the catalyst particle which mainly occurs from CH4 decomposition reaction. Coke formation leads to a decrease in catalytic performance by blocking the pores and active sites. In this study, the spatial catalyst deactivation caused by coke formation over a spherical alumina-supported nickel catalyst (Ni/Al2O3) particle in dry reforming of methane (DRM) was investigated using …
Use Of Polyacrylonitrile As Anodic Artificial Solid Electrolyte Interphase For Aqueous-Based Zinc-Ion Batteries, Nutchaya Muangplod
Use Of Polyacrylonitrile As Anodic Artificial Solid Electrolyte Interphase For Aqueous-Based Zinc-Ion Batteries, Nutchaya Muangplod
Chulalongkorn University Theses and Dissertations (Chula ETD)
Rechargeable aqueous zinc-ion batteries (ZIBs) have attracted attention for energy storage systems because of their high specific capacity, low cost, and safety. However, practical application of the zinc anode in mild acidic electrolytes is limited by several issues such as dendrite formation, corrosion, hydrogen evolution reaction, passivation and relatively low cycling performance. Coating the zinc anode with graphite (GP) (GP@Zn) can partially solve these issues and improves the cycling performance of ZIB. However, after long-term charge/discharge cycles, zinc tends to migrate and redeposit over the surface of GP owing to the electronic conductivity of GP particles. Thus, after long-term cycling, …
Manganese Dioxide Coated With Tin Oxide As Cathode Material For High-Performance Aqueous Zinc-Ion Battery., Nichakarn Meekaew
Manganese Dioxide Coated With Tin Oxide As Cathode Material For High-Performance Aqueous Zinc-Ion Battery., Nichakarn Meekaew
Chulalongkorn University Theses and Dissertations (Chula ETD)
Rechargeable aqueous zinc-ion batteries (ZIBs) have attracted increasing attention as an energy storage technology due to their high energy density, low cost, and environmental friendliness. However, the application of manganese dioxide as the cathode for aqueous Zn-ion batteries (ZIBs) is restricted by the solubility of manganese dioxide in aqueous electrolytes and the formation of byproducts during the charge/discharge process, causing severe capacity fading and limited cycle life. Surface modification is one of the interesting techniques to improve zinc-ion batteries electrochemical performance. Here, we report an ultrathin SnO2 film as an artificial solid electrolyte interphase (SEI) to modify the surface of …
Cathodized Stainless Steel Mesh For Binder-Free Nife2o4/Nife Ldh Oxygen Evolution Reaction Electrode, Natthapon Sripallawit
Cathodized Stainless Steel Mesh For Binder-Free Nife2o4/Nife Ldh Oxygen Evolution Reaction Electrode, Natthapon Sripallawit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Oxygen evolution reaction (OER) is an essential reaction commonly applied in various energy storage and conversion technologies. One of the common issues of OER lies in its low kinetic activity. Therefore, developing durable, low-cost, and high-performance OER catalysts is critical. Recently, many attempts have used stainless steel mesh (SSM) as the substrate for OER electrodes because SSM is abundant, cheap, and durable. Nickel/iron-based materials, i.e., NiFe2O4/NiFe layer double hydroxides (LDHs), are regarded as one of the most excellent OER catalysts in alkaline electrolytes, making them attractive low-cost materials for OER catalysts. However, the synthesis of NiFe2O4/NiFe LDHs directly on the …
Norfloxacin Adsorption By Activated Carbon From Turmeric Waste, Nuttamon Vanichsetakul
Norfloxacin Adsorption By Activated Carbon From Turmeric Waste, Nuttamon Vanichsetakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In recent years, extensive use of modern medicines and incompetency of conventional wastewater treatment systems have led to contamination of antibiotics in the environment especially in lower income countries. Antibiotics could interact with bacteria in the environment forming resistance to the medicine. Antibiotics also disrupt the balance of ecosystems affecting various lifeforms. Norfloxacin is a common antibiotic in Thailand with reported levels of contamination in Bang Pakong River. Adsorption process is a cheap and effective approach to remove antibiotics from wastewater effluent. Activated carbon is a common adsorbent in adsorption process due to its porous properties. Agricultural waste presents as …
Electrochemical Tubular Fixed-Bed Reactor For Conversion Of Pressurized Co2 To Co, Pakawat Sengchim
Electrochemical Tubular Fixed-Bed Reactor For Conversion Of Pressurized Co2 To Co, Pakawat Sengchim
Chulalongkorn University Theses and Dissertations (Chula ETD)
Electrochemical CO2 reduction reaction (CO2RR) can be used for activating the stable CO2 molecule to the more active CO for downstream purposes. Usually, this process is carried out in CO2-saturated aqueous solutions. The low solubility of CO2 in water of 0.033 M at 1 bar of CO2 and room temperature hinders both kinetics and mass transfer. In this study, a novel electrochemical tubular reactor for electrochemical CO2RR is proposed. The design was made with ease of scale-up in mind. A reactor can contain multiple electrochemical cells connected in series. Each cell consists of 3 main parts: porous anode, porous solid …
Tetracycline Sorption By Magnetic Biochar Derived From Watermelon Rind: Performance And Influential Factors, Phisit Thairattananon
Tetracycline Sorption By Magnetic Biochar Derived From Watermelon Rind: Performance And Influential Factors, Phisit Thairattananon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Tetracycline (TC) antibiotic is one of emerging contaminants in water reservoirs that causes undesirable effects on environment and human health. Magnetic biochar (MBC) is considered a promising sorbent in adsorption process for removal of contaminants with highly efficient and facile operation. In this work, MBC was synthesized by pyrolysis of watermelon rind impregnated with FeCl3 at different pyrolysis temperatures in a range of 600-900 °C prior to applying for TC adsorption. Characteristics of MBC were analyzed by scanning electron microscopy, elemental analyzer, N2 adsorption/desorption, Fourier-transform infrared spectroscopy, Raman spectroscopy, vibrating sample magnetometry, and X-ray diffractometry. The adsorption kinetics, isotherm, effect …
Effect Of Bismuth (Bi) Concentration On Bi/Sn Electrodes Prepared By Electrodeposition In Electrochemical Reduction Of Co2 To Toward Solid Carbon Products, Sarita Phupaichitkun
Effect Of Bismuth (Bi) Concentration On Bi/Sn Electrodes Prepared By Electrodeposition In Electrochemical Reduction Of Co2 To Toward Solid Carbon Products, Sarita Phupaichitkun
Chulalongkorn University Theses and Dissertations (Chula ETD)
Carbon dioxide (CO2) is the main greenhouse gas that contributes to climate change. The electrochemical carbon dioxide reduction (CO2RR) is an interesting and low-cost CO2 conversion technology using renewable electricity as an energy source. Herein, CO2RR to solid carbon products was studied on bismuth/tin (Bi/Sn) electrodes synthesized by electrodeposition method. Different Bi concentration (0.01 M,0.03 M, 0.05 M,0.07 M and 0.1 M) were used to prepare the electrodes by electrodeposition method. The SEM-EDX and EIS results which reveal that the Bi/Sn electrode prepared in 0.05 M Bi 3+ had the lowest charge transfer resistance and was indicated as a CO2RR …
Preparation Of Nickel Phyllosilicate Catalysts By One-Step Modified Spherical Silica Synthesis In Carbon Dioxide Hydrogenation And Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Sasithorn Kuhaudomlap
Preparation Of Nickel Phyllosilicate Catalysts By One-Step Modified Spherical Silica Synthesis In Carbon Dioxide Hydrogenation And Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Sasithorn Kuhaudomlap
Chulalongkorn University Theses and Dissertations (Chula ETD)
Spherical silica derived nickel phyllosilicate catalysts were prepared via a one-step modified spherical silica synthesis under room temperature. For 10wt% Ni loading, the loading sequence of Ni and Si sources during spherical silica synthesis was found to affect the characteristics and catalytic properties in CO2 methanation. The stronger interaction between Ni and silica in the form of nickel phyllosilicate revealed the better catalytic performances than the impregnation method. The highest CO2 methanation activity and methane selectivity were obtained over the catalyst prepared by alternate loading between Ni and Si (Ni_Alt_Si) due to high electron density of nickel on the surface, …
Liquid-Phase Selective Hydrogenation Of Furfural To Furfuryl Alcohol Over Pt- And Ptfe-Incorporated Mesoporous Carbon, Sureeporn Saknaphawuth
Liquid-Phase Selective Hydrogenation Of Furfural To Furfuryl Alcohol Over Pt- And Ptfe-Incorporated Mesoporous Carbon, Sureeporn Saknaphawuth
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aims to investigate the liquid-phase selective hydrogenation of furfural to furfuryl alcohol in a batch reactor at 50ºC, 20 bar H2 using water and methanol as the solvent. This study has been divided into two sections. The characteristics and catalytic properties of OMC-supported Pt catalysts (Pt/OMC-one-pot) prepared by one-step modified soft-template self-assembly method were compared with the Pt impregnated on OMC, activated carbon (AC), and non-uniform meso/macroporous carbon (MC) in the first section. Larger Pt particle size (~4 nm) was obtained on the Pt/OMC-one-pot comparing to all the impregnated ones, in which the Pt particle sizes were in …
Synthesis Of Magnetic Carbon Nanotubes Via Co-Pyrolysis Of Eucalyptus Oil With Bimetallic Ni-Fe Catalyst, Tanapat Rodruangnon
Synthesis Of Magnetic Carbon Nanotubes Via Co-Pyrolysis Of Eucalyptus Oil With Bimetallic Ni-Fe Catalyst, Tanapat Rodruangnon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Magnetic carbon nanotubes (MCNTs) have been specified one of the most promising nanomaterials. They have been applied in many applications due to special electrical, mechanical, and chemical properties. Additionally, magnetic carbon nanotubes could be easily handled by using magnetic field. There are many production developments for increasing in yield and quality of MCNTs. In this thesis, bimetallic Ni-Fe catalyst was investigated for its possibility to improve MCNT synthesis. Nickel content was impregnated on the surface of ferrocene which is the source of Fe content. The catalyst is called ‘ferrocene impregnated with nickel nitrate’. Eucalyptus oil, which mainly contains eucalyptol, was …
Development Of Nonaqueous Zinc-Ion Battery Based On Manganese Dioxide Cathode, Wathanyu Kao-Ian
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 …
Quality Control Of Chemical Grade Calcium Carbonate From Lopburi Limestone Deposit In Thailand, Pimpichcha Teawpanich
Quality Control Of Chemical Grade Calcium Carbonate From Lopburi Limestone Deposit In Thailand, Pimpichcha Teawpanich
Chulalongkorn University Theses and Dissertations (Chula ETD)
Calcium carbonate (CaCO3) is naturally produced from calcite, limestone, chalk, and marble. It is being used as raw material in various industries (e.g., cement, plastic, paint, paper, and pharmaceutical industries). The low-grade CaCO3 samples obtained from a calcite plant at Khoktum Sub-district, Muang Lopburi District, Lopburi Province, Thailand were used in this study. These samples contain more than 98% of CaCO3 while Fe2O3 contents are higher than 0.1% and increased after finished the process. Because of this problem, the products could not be sold since lower Fe2O3 contents are required (e.g., ≤0.05% for filler grade and ≤ 0.1% for animal …