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Articles 13801 - 13830 of 15281
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Effects Of Titanium Dioxide Structure And Cobalt Addition On The Catalytic Properties Of Ru/Tio2 In The Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Natdanai Nanthasanti
Effects Of Titanium Dioxide Structure And Cobalt Addition On The Catalytic Properties Of Ru/Tio2 In The Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Natdanai Nanthasanti
Chulalongkorn University Theses and Dissertations (Chula ETD)
Furfuryl alcohol, an important intermediate for the production of many fine chemicals, is typically produced by the selective hydrogenation of lignocellulosic biomass-derived furfural using supported metal catalysts. In this research, 1.5%wt Ru catalysts supported on nanocrystalline TiO2 were prepared by incipient wetness impregnation method. The effects of crystallographic of TiO2 and Co addition in the range of 0.2-0.8 wt% on the catalytic properties of Ru/TiO2 were investigated in the selective hydrogenation of furfural to furfural alcohol at 50°C, 20 bar of H2, and 2 h reaction time. It was found that Ru supported on anatase phase TiO2 exhibited the highest …
Dehydration Of Ethanol Over Zsm-5 Catalysts Having Different Si/Al Molar Ratios With H3po4 And Pd Modification, Nattawat Nampipat
Dehydration Of Ethanol Over Zsm-5 Catalysts Having Different Si/Al Molar Ratios With H3po4 And Pd Modification, Nattawat Nampipat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Dehydration of ethanol was studied over ZSM-5, HZSM-5 and modified HZSM-5 catalysts under atmospheric pressure and temperature range of 200 °C to 400 °C. ZSM-5 catalysts were prepared by hydrothermal method using tetraphopylammonium bromide, sodium silicate solution and aluminium nitrate nonahydrate. The results showed that the various Si/Al molar ratios led to affect the amount of acidity on the surface of catalysts. The ZSM-5(20) catalyst exhibited the highest ethanol conversion at 400 °C about 70.3 % due to its high acid sites and large surface area. The commercial HZSM-5 catalysts, which had molar ratio similar to ZSM-5 Si/Al 20 catalysts, …
Ethylene Polymerization Over Cellulose-Supported Modified Methylaluminoxane/Zirconocene Catalyst, Natthadabhorn Thanarattanasap
Ethylene Polymerization Over Cellulose-Supported Modified Methylaluminoxane/Zirconocene Catalyst, Natthadabhorn Thanarattanasap
Chulalongkorn University Theses and Dissertations (Chula ETD)
Presently, the polyethylene has been profusely applied in the several industries, for instance manufacturing of pipe, film and plastic bags. In polyethylene production, there are two catalysts which are used in production, including Ziegler-Natta catalyst and metallocene catalyst. The metallocene catalyst is immobilized by support and activated by cocatalyst. For the support of metallocene catalysts, both of inorganic and organic supports are applied and in this research study, cellulose which is organic support for metallocene catalyst, was used. Since, cellulose is extensively used biopolymer representing a great deal of total annual biomass production. Due to environmental issues, natural materials have …
Effects Of Pbs Quantum Dot Doped Tio2 Nanotubes As Electron Transporting Layer On The Efficiency Of Perovskite Solar Cells, Natthapat Rattanawichai
Effects Of Pbs Quantum Dot Doped Tio2 Nanotubes As Electron Transporting Layer On The Efficiency Of Perovskite Solar Cells, Natthapat Rattanawichai
Chulalongkorn University Theses and Dissertations (Chula ETD)
TiO2 nanotubes (TNTs) are used as an excellent electron transporting layer for high efficiency perovskite solar cells. In this work, TNTs were synthesized via hydrothermal process from different particle sizes of TiO2 nanoparticle precursors as follows: 5 nm, 25 nm, and 50 nm. The highest surface area of 312.39 m2/g of TNTs was obtained from TiO2 precursor with particle size of 25 nm and was used to dope with lead sulfide quantum dots (PbS QDs). Due to a large band gap and poor conductivity of TNTs which limits the efficiency to transport electrons in the perovskite solar cell, PbS QDs …
Hydrogen Production From Biogas By The Combined Process Of Chemical Looping Water Splitting And Sorption Enhanced Reforming Process: Process Analysis And Design, Natthaporn Saithong
Hydrogen Production From Biogas By The Combined Process Of Chemical Looping Water Splitting And Sorption Enhanced Reforming Process: Process Analysis And Design, Natthaporn Saithong
Chulalongkorn University Theses and Dissertations (Chula ETD)
The integrated sorption-enhanced chemical looping reforming and water splitting (SECLR-WS) process was proposed for hydrogen (H2) production from biogas using iron oxide as the oxygen carrier and calcium oxide (CaO) as a carbon dioxide (CO2) adsorbent. The simulation of the SECLR-WS process was based on a thermodynamic approach and was performed using an Aspen Plus simulator. The sensitivity results showed that the H2 yield (mole of H2/mole of CH4), H2 purity in the fuel reactor (FR), and CH4 conversion could be improved by increasing the steam feed to the FR to CH4 (SFR/CH4) and CaO to CH4 (CaO/CH4) molar ratios. …
Improving Fouling Resistance Of Thin Film Composite Membranes By Addition Of Tio2, Palach Kedchaikulrat
Improving Fouling Resistance Of Thin Film Composite Membranes By Addition Of Tio2, Palach Kedchaikulrat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polyamide thin film nanocomposite (TFN) membranes with the addition of titanium dioxide (TiO2) nanoparticles (NPs) were synthesized via an interfacial polymerization (IP) on polyacrylonitrile (PAN) support. Also, the TFC membranes with addition of individual components in the TiO2 colloidal solution, ethanol, TiO2 NPs and nitric acid, were individually studied. The performances of the fabricated membranes were evaluated in terms of NaCl salt rejection, water permeability and anti-fouling capability. Membranes characterizations were conducted to observe various characteristics of membranes such as morphology, surface roughness, surface chemistry and hydrophilicity. The results revealed that the addition of TiO2 colloidal solution in aqueous amine …
Determination Of Mass Transfer Coefficient Of Co2 In Solutions Of Monoethanolamine, 2-(Methylamino)Ethanol And Dimethylaminoethanol In Packed Absorption Column, Parintorn Vaewhongs
Determination Of Mass Transfer Coefficient Of Co2 In Solutions Of Monoethanolamine, 2-(Methylamino)Ethanol And Dimethylaminoethanol In Packed Absorption Column, Parintorn Vaewhongs
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, mass transfer of two new solvents, 2-MAE and DMAE were studied with various factors affecting mass transfer coefficient in comparison with MEA. Effect of solvent types, CO2 inlet loading 0.0, 0.1 and 0.2 mol/mol, solvent concentration 3, 4 and 5 kmol/m3, solvent flow rate 5.3, 10.6 and 15.9 m3/(m2·h) and CO2 content 13-15 v/v% in gas feed were investigated. In all cases, 2-MAE performed highest mass transfer rate among others. The highest mass transfer rate was 1.2656 kmol/(kPa·h·m3) for the case that CO2 inlet loading 0.0 mol/mol, solvent concentration 3 kmol/m3, solvent flow rate 10.6 m3/(m2·h) and …
Development Of Starch-Nanocellulose Composites For Using In Surface Treatment Of Paper, Phanthakan Ow
Development Of Starch-Nanocellulose Composites For Using In Surface Treatment Of Paper, Phanthakan Ow
Chulalongkorn University Theses and Dissertations (Chula ETD)
The main role of surface sizing is to increase the surface strength of paper. Starch is commonly used as surface sizing agents, but there are still some limitations. In this study, nano-bacterial cellulose (NBC) produced by Acetobacto xylinum was used as a reinforcing material in starch-based composites. The suspensions of NBC starch-based composites were prepared by the additions of 0.10-10.00% w/w NBC into starch solution and were used as surface sizing agents. The structures and properties of NBC starch-based composite films were characterized by FTIR, XRD, and SEM. The mechanical properties and barrier properties of cellulosic paper with surface sizing …
Continuous Hydrotreating Process Of Palm Fatty Acid Distillate (Pfad) Over Bimetallic Nicu/Hzsm-5 Catalyst For Bio Jet Fuel Production, Phisit Wirikulcharoen
Continuous Hydrotreating Process Of Palm Fatty Acid Distillate (Pfad) Over Bimetallic Nicu/Hzsm-5 Catalyst For Bio Jet Fuel Production, Phisit Wirikulcharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated bimetallic NiCu/HZSM-5 catalyst for the production of bio jet fuel via hydrotreating process. The catalysts with different Ni and Cu ratio were characterized by XRD, NH3-TPD, H2-TPR, SEM-EDX and N2-physisorption techniques. Palm fatty acid distillate (PFAD), nonedible by-product from palm oil refining process, was employed as a low-cost feedstock. For catalyst screening, the reaction was performed in an autoclave reactor under batch operation with operating temperature of 375°C, initial H2 pressure of 50 bars and reaction time of 3 h. The results showed that doping Cu could enhance deoxygenation activity while carbon formation was found to be …
Preparation Of Stable Hydrothermal Carbon-Based Catalyst From Defatted Rice Bran And Glucose For Biomass Conversion To 5-Hydroxymethylfurfural, Piyaporn Wataniyakul
Preparation Of Stable Hydrothermal Carbon-Based Catalyst From Defatted Rice Bran And Glucose For Biomass Conversion To 5-Hydroxymethylfurfural, Piyaporn Wataniyakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the preparation of hydrothermal carbon-based catalysts (HTC-SO3H) derived from defatted rice bran (DRB) and glucose for biomass conversion to 5-hydroxymethylfurfural (HMF). Firstly, the effects of hydrothermal carbonization conditions: temperature (180-250 °C) and time (1-8 h) on the yield and the chemical characteristics of the hydrothermal carbons (HTCs) were investigated. The HTCs were then sulfonated with sulfuric acid to obtain HTC-SO3H catalysts. The stability of the catalysts was evaluated based on the amount of biomass conversion products leached into the water at a specified biomass conversion condition. Since no HMF and furfural, and only small amounts of levulinic …
Effects Of Titania Phase And Tungsten Loading Content In W/Tio2 Catalysts On Dehydration Of Ethanol To Diethyl Ether, Pongsatorn Kerdnoi
Effects Of Titania Phase And Tungsten Loading Content In W/Tio2 Catalysts On Dehydration Of Ethanol To Diethyl Ether, Pongsatorn Kerdnoi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, ethanol which is one of the most used renewable energies can be converted into the more valuable compounds. It was reported that titania-supported tungsten (W/TiO2) catalyst is able to convert ethanol into diethyl ether. However, titania support has different crystalline phases that can result in differences of physicochemical properties for the catalyst. Therefore, the present work reports on the catalytic behaviors of both different phases of titania and tungsten loading contents in catalytic ethanol dehydration to diethyl ether. To prepare the catalysts, the three different phases [anatase (A), rutile (R), and mixed phases (P25)] of titania supports were impregnated …
Modification Of Titanium Dioxide With Nitrogen, Silicon, And Carbon For Visible Light Photocatalysis, Rachan Klaysri
Modification Of Titanium Dioxide With Nitrogen, Silicon, And Carbon For Visible Light Photocatalysis, Rachan Klaysri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Titanium dioxide and nitrogen-silicon-codoped titanium dioxide were prepared by two different ways. The first method was prepared by using nitrogen as a nitrogen source and silicon-containing chemical as a silicon source via solvothermal- and sol-gel-made photocatalysts. The nitrogen-silicon-codoped titanium dioxide showed the highest photocatalytic activity under both UV and visible light irradiation. The addition of silicon resulted in the formation of partial monolayer of silicon on titanium dioxide and an increase of the anatase phase stability. The annealing atmosphere affected the distribution concentration of surface and interface species such as surface oxygen and Ti3+ sites, thus improving photocatalytic activity. Moreover, …
A Study Of Catalyst Type And Dispersion On Pyrolysis Of High Density Polyethylene, Ratchanon Chantanuson
A Study Of Catalyst Type And Dispersion On Pyrolysis Of High Density Polyethylene, Ratchanon Chantanuson
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study of catalyst type and dispersion on pyrolysis of high density polyethylene (HDPE) was investigated in batch and semi-batch reactor system. The separation system in semi-batch was rapidly separated between oil and gas products while in batch system was separated after cooling down process. The obtained oil products in semi-batch system had higher in short-chain hydrocarbon. Because the increased pressure and the high severity in batch system led to occur side reactions. Two types of catalyst were studied, Cat A was acid catalyst with 200 m2/g surface area and 20 A average pore diameter and HZSM-5 zeolite was stronger …
Effect Of Amino Propanol Structure On Carbon Dioxide Absorption, Rossukon Nimcharoen
Effect Of Amino Propanol Structure On Carbon Dioxide Absorption, Rossukon Nimcharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, global warming is the main issue on environmental concern due to the higher amount of carbon dioxide (CO2) in the atmosphere.The current technology to remove CO2 effectively is carbon capture and storage or CCS, especially absorption with aqueous amine solutions. The commonly used amine solutions are monoethanolamine (MEA). They have some disadvantages like low capacity. Therefore, a new solvent such as 3-amino-1-propanol (3A1P), 3-dimethylamino-1-proapnol (3DMA1P) and 1-dimethylamino-2-proapnol (1DMA2P) have been designed to be used as alternative solvents for CO2 removal. In this work, the solubility of carbon dioxide in new promising solvents. The effect of solvent concentration is studied …
Improving The Efficiency Of Dye-Sensitized Solar Cells With Spray-Coated Tio2 Electrode Modified By Cuo, Nio, Or In2o3, Sakun Preedavijitkul
Improving The Efficiency Of Dye-Sensitized Solar Cells With Spray-Coated Tio2 Electrode Modified By Cuo, Nio, Or In2o3, Sakun Preedavijitkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the application of the CuO/TiO2, NiO/TiO2, or In2O3/TiO2 thin film electrode in dye-sensitized solar cells (DSSCs). Second metal oxide and TiO2 sols were synthesized separately via sol-gel methods. The sols were mixed and sprayed onto the fluorine-doped tin oxide glass substrates. The amount of second metal oxide added to TiO2 was varied at 0, 0.1, 0.5, 1.0, and 3.0%wt. The electrode layer was sintered at 400˚C for two hours. The addition of CuO, NiO, and In2O3 produced the photovoltaic efficiency of the cell 4.03±0.58% with 0.1%wt. CuO/TiO2, 5.17±0.07% with 0.5%wt. NiO/TiO2, and 6.21±0.87% with 1.0%wt. In2O3/TiO2, respectively. …
Comparison Of Zsm - 5 And Poss Nanocomposite Pervaporation Membranes For Furfural/Water Separation, Seth Sawatdiruk
Comparison Of Zsm - 5 And Poss Nanocomposite Pervaporation Membranes For Furfural/Water Separation, Seth Sawatdiruk
Chulalongkorn University Theses and Dissertations (Chula ETD)
The recovery of furfural via a conventional separation technology like distillation and solvent extraction requires very large energy consumption and high amount of chemical solvent. Thus, there is a need for an alternative separation process that is economic and more energy friendly for the furfural recovery. Pervaporation is a well - recognized energy friendly and effective separation tool. If there is suitable pervaporation membrane with efficient separation performance, the pervaporation can be a promising replacement for the conventional separation method. Therefore, this thesis aims to develop a suitable membrane for furfural recovery via pervaporation process. In this work, the polydimethylsiloxane …
Development Of Graphite/Graphene/Carbon Nanotubes Filled Benzoxazine Composites For Bipolar Plates In Fuel Cell Applications, Sirawit Witpathomwong
Development Of Graphite/Graphene/Carbon Nanotubes Filled Benzoxazine Composites For Bipolar Plates In Fuel Cell Applications, Sirawit Witpathomwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aims to develop bipolar plate from polymer composite to be used in proton exchange membrane fuel cells. The key properties of bipolar plates include high thermal conductivity, high electrical conductivity, high flexural strength and modulus, and low water absorption. The polybenzoxazine composites having three types of carbon derivatives i.e. graphite, graphene, and carbon nanotubes were prepared using a compression molder with a pressure of 15 MPa and a temperature of 200oC for 2 hours. The effects of carbon nanotube contents varying from 0-2wt% at an expense of graphite with constant content of graphene and benzoxazine at 7.5 and …
Effect Of Palm Fatty Acid Distillate On Hydrodesulfurization And Hydrodeoxygenation In Co-Processing With Petroleum Gas Oil In Hydrotreating Unit, Sunya Boonyasuwat
Effect Of Palm Fatty Acid Distillate On Hydrodesulfurization And Hydrodeoxygenation In Co-Processing With Petroleum Gas Oil In Hydrotreating Unit, Sunya Boonyasuwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Deoxygenation of palm fatty acid distillate (PFAD) to produce renewable diesel had been experimented in co-processing with petroleum light gas oil (LGO) in a pilot-scale reactor. The reaction was achieved in the fixed-bed hydrotreating reactor, over commercial CoMo/Al2O3 under 280-350 oC, 25 barg, H2/feed of 630 Nm3/m3 and 0.75 h-1 of LHSV. High conversion were achieved when varied PFAD up to 25 wt%. The presence of PFAD in LGO improved cetane index of the liquid products. Heat effect due to overall exothermic reactions was observed. Hydrogen consumption was then theoretically calculated and extrapolated for hydrotreating of pure PFAD. Further study …
The Effect Of Adsorption On Photocatalytic Degradation Of Phenyl Urea Herbicides On Zinc Oxide, Sutaporn Meephon
The Effect Of Adsorption On Photocatalytic Degradation Of Phenyl Urea Herbicides On Zinc Oxide, Sutaporn Meephon
Chulalongkorn University Theses and Dissertations (Chula ETD)
The effect of adsorption on photocatalytic degradation was studied by using zinc oxide with different morphologies and exposed surfaces as the photocatalyst. Polar zinc-terminated surface and polar oxygen-terminated surface are dominating planes on the top and bottom of a crystal of ZnO conventional particles, while non-polar surface is the main plane on the side of ZnO nanorods. These surfaces affect the adsorption behavior of phenylurea herbicides, i.e. diuron, linuron and 3,4-dichloroaniline. Consequently, they cause the difference in photocatalytic degradation rate and intermediate products formed during the degradation. The adsorption capacity of ZnO conventional particles is about twice as high as …
Performance Comparison Of Multifunctional Reactors For Biodiesel Production From Transesterification Of Palm Oil, Tanutporn Laosuttiwong
Performance Comparison Of Multifunctional Reactors For Biodiesel Production From Transesterification Of Palm Oil, Tanutporn Laosuttiwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biodiesel is classified as a qualified alternative energy that can be used for diesel engine. It is produced via transesterification of vegetable oil with alcohol in presence of homogeneous or heterogeneous catalyst. However, oil and alcohol are not totally miscible leading to slow reaction rate. Multifunctional reactors, especially cavitational reactors, are proposed to overcome this issue. The cavitational reactors include ultrasonic reactor and homogenizer reactor. In this work, ultrasonic reactor, homogenizer reactor and conventional magnetic stirred reactor were used to investigate and compare biodiesel yield and the efficiency in terms of biodiesel yield based on the energy consumption at different …
Effects Of Modification Of Γ-Al2o3 Support By La And Ce On Pt Dispersion And Oxygen Mobility For Co Oxidation, Thanawat Wandondaeng
Effects Of Modification Of Γ-Al2o3 Support By La And Ce On Pt Dispersion And Oxygen Mobility For Co Oxidation, Thanawat Wandondaeng
Chulalongkorn University Theses and Dissertations (Chula ETD)
Effects of La or Ce modified Pt/γ-Al2O3 catalysts on Pt dispersion and oxygen mobility of catalyst were investigated by CO oxidation reaction. 0, 0.01, 0.05, 0.10 and 0.15 molar ratio of La or Ce to Al was doped on Pt/γ-Al2O3 catalysts (0.3wt%Pt) by impregnation method. The CO oxidation activities in terms of light-off temperature (T50) and turnover frequencies (TOF) corresponded to Pt dispersion, oxygen mobility as characterized by various analytical techniques such as X-ray diffraction (XRD), N2-physisorption, CO-pulse chemisorption, and temperature programed desorption of CO2 (CO2-TPD). The results indicated that the addition of La on Pt/γ-Al2O3 catalysts increased the dispersion …
Effect Of Operating Variables Of Corona Discharge Reactor Onbenzene Removal Efficiency, Thanunwut Thanahirunthitichote
Effect Of Operating Variables Of Corona Discharge Reactor Onbenzene Removal Efficiency, Thanunwut Thanahirunthitichote
Chulalongkorn University Theses and Dissertations (Chula ETD)
Volatile organic compound (VOC) has been known as one of air pollutants generated by the fast growth of industry and social development. There were many kind of VOC which is harmful for humans and environments. All concerned organization requested controlling of these problems. As a result, there were many technologies developed for handling and degrading such VOC. Among these technologies, corona discharge reactor has been known as a promising means because of its effectiveness and compactness. In this work, benzene was selected as a model VOC pollutant. Performance of multi-channeled corona discharge reactor for removal of benzene was experimentally examined …
Chromatographic Separation Of Free Lutein And Fatty Acids In De-Esterified Marigold Oleoresin And Its Mathematical Modelling, Weerawat Clowutimon
Chromatographic Separation Of Free Lutein And Fatty Acids In De-Esterified Marigold Oleoresin And Its Mathematical Modelling, Weerawat Clowutimon
Chulalongkorn University Theses and Dissertations (Chula ETD)
The petal of marigold flowers has been reported to be the richest source of a xanthophyll, namely lutein which exhibits strong antioxidant and anticancer properties. Although large amount of lutein can be obtained, the compound in the flowers exists as esterified lutein, which is not readily bio-available. As a result, a number of separation and purification steps are required after solvent extraction of marigold flowers. One of the key steps is de-esterification of lutein fatty acid esters in the extract, or namely marigold oleoresin, by the reaction of the oleoresin with alkali solution, e.g., KOH, to obtain free lutein. The …
Catalytic Hydrogenation Of Carbon Dioxide For Hydrocarbon Synthesis, Nuttakorn Boreriboon
Catalytic Hydrogenation Of Carbon Dioxide For Hydrocarbon Synthesis, Nuttakorn Boreriboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Catalytic hydrogenation can turn CO2 into hydrocarbon fuel. The development of the catalysts for CO2 hydrogenation has become important since the catalysts are critical for selective production of more higher hydrocarbons for practical application. In this work, the titania supported monometallic and bimetallic Fe-M (M = Co and Cu) catalysts were synthesized and tested for CO2 hydrogenation at 573 K and 1.1 MPa. Among the monometallic catalysts (Fe, Co and Cu/TiO2), only Fe/TiO2 catalyst exhibited some selectivity to higher hydrocarbons, while Co/TiO2 and Cu/TiO2 catalysts were highly selective only to CH4 and CO, respectively. The addition of a small amount …
Hydrogen Rich Gas Production From Pyrolysis-Gasification Of Biomass With Combined Catalyst And Sorbent, Teerayut Bunma
Hydrogen Rich Gas Production From Pyrolysis-Gasification Of Biomass With Combined Catalyst And Sorbent, Teerayut Bunma
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, the hydrogen production during biomass steam pyrolysis-gasification with a combined catalysts and sorbent (catalyst/sorbents) was studied in a drop tube two-stages fixed bed reactor. The catalyst/sorbents were prepared by an excess-solution impregnation method. A nickel oxide (NiO)/magnesium oxide (MgO)/calcium oxide(CaO) catalyst/sorbents containing 10 wt. % NiO, 5 wt. % MgO and 5 wt. % CaO on gamma alumina (γ-Al2O3) showed the best activity in sorption enhanced hydrogen production (SEHP) for the pyrolysis-gasification of sugarcane leaves. Besides, the highest H2 concentration and the lowest CO2 concentration were attained using the Mg5Ni10Ca5 catalyst/sorbents. Because Mg5Ni10Ca5 catalyst/sorbents provided the dominant …
Synthesis Of Bi- And Trifunctional Mesoporous Silica-Based Catalyst And Application In One-Pot Cascade Reactions, Apichat Klayanon
Synthesis Of Bi- And Trifunctional Mesoporous Silica-Based Catalyst And Application In One-Pot Cascade Reactions, Apichat Klayanon
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work reports the synthesis and full characterization of bifunctional mesoporous silica supported acid (-SO3H)-base (-NH2) catalysts and trifunctional mesoporous silica supported acid-base-metal catalysts as well as their applications. A series of bifunctional catalysts were synthesized with different site separations, acid loadings, base loadings and types of aminosilane, namely N2SA2, SA0.5N0.5, SA0.5N2, SA1N2, SA2N2, SA0.5N4, SA0.5NN4 and SA0.5NNN4, via a co-condensation and post-synthetic grafting methods and were characterized by XRD, FT-IR, N2 adsorption-desorption, SEM, TEM, TGA and XPS techniques. The well-ordered hexagonal mesoporous structure was preserved throughout the synthesis where the synthesized materials exhibited small kidney-bean-shaped rod and highly ordered …
Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham
Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham
Chulalongkorn University Theses and Dissertations (Chula ETD)
Novel nanomaterial sensors have been designed two different strategies of sensing approach. The first sensing system, the aggregation nanomicelles (TSC and TSD) were synthesized for GSH sensing based on disulfide-cleavaged trigger in the micelle. The result showed a large quenching fluorescent intensity around 587 nm and 528 nm corresponding to TSC and TSD, respectively, upon the addition of GSH in 2.5% DMSO/PBS at pH 6. Additionally, the benefit of TSD is utility for the distance-based fluorescence detection of 3D paper analytical device (3D-µPAD) for the detection of GSH. Apart from GQDs sensors base, we demonstrated the utility and board applicability …
Photocatalytic Conversion Of Glycerol To Dihydroxyacetone, Trin Jedsukontorn
Photocatalytic Conversion Of Glycerol To Dihydroxyacetone, Trin Jedsukontorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work was carried out to convert glycerol to value-added compounds in liquid phase over TiO₂-based photocatalyst. The investigated parameters were catalyst dosage (1-3 g/L), H₂O₂ concentration (0.3-1.5 mol/L), UV light intensity (1.1-4.7 mW/cm²), reaction time (4-8 h) and electron acceptor types (O₂ and H₂O₂). It was found that TiO₂ in anatase phase can achieved the glycerol conversion of around 71.42% at catalyst dosage of 3 g/L, H₂O₂ concentration of 1.5 mol/L, UV light intensity 4.7 mW/cm² and reaction time 8 h. The addition of monometallic (bismuth, platinum, palladium, and gold) and bimetallic (gold-bismuth, gold-platinum, and gold-palladium) on TiO₂ can …
Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul
Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Pyrrolidinyl peptide nucleic acid bearing D-prolyl-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) is a nucleic acid mimic that shows superior binding affinity, stability and specificity to complementary DNA than the original PNA. This research focuses on the development of hybridization responsive fluorescence acpcPNA probes bearing fluorescent nucleobases that exhibit fluorescence increase upon hybridization to a specific nucleobase in the DNA target. The acpcPNA carrying the fluorescent nucleobases were synthesized via two different approaches, namely 1) pre-synthesized fluorescence PNA monomer as a building block that was subsequently incorporated into the PNA by solid phase synthesis and 2) post-synthetic modification of acpcPNA carrying a reactive …
Application Of Headspace-Gas Chromatography-Mass Spectrometry For Characterization Of Volatile Compounds In Chicken Eggs, Hanan Jehma
Chulalongkorn University Theses and Dissertations (Chula ETD)
Volatile compounds in chicken eggs under the cold chain system and non-cold chain system were characterized by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with chemometrics. According to a central composite design, the following optimum HS-SPME extraction conditions were obtained: extraction temperature of 65 oC, extraction time of 45 min and the amount of NaCl of 0.4 g. In comparison of their mass spectrum and linear retention index from HS-SPME-GC-MS analysis, major volatile compounds found in egg samples included toluene, hexanal, nonanal and other minor volatile compounds were heptanal, octanal, decanal, benzaldehyde, 1-octen-3-ol and 2-ethyl-1-hexanol, with the types and amounts …