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Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol
Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this research was to study the optimal condition for chicken feather meal protein hydrolysate production using a microbial protease, Protease G6. The experimentation was conducted using Central Composite Design (CCD) and Response Surface Methodology (RSM). The three independent variables including temperature (°C), time and enzyme-substrate ratio were studied. Optimization process for obtaining high yield of chicken feather meal protein hydrolysate was performed using response surface methodology (RSM) by optimizing a combination of three independent variables namely, temperature (41.59 – 58.41°C), time (0:38 - 7:21 h) and enzyme-substrate ratio (0.8 – 9.2) with degree of hydrolysis (DH) as …
Tyrosinase Inhibitors From Sapodilla Plum Manilkara Zapota L., Sutthiduean Chunhakant
Tyrosinase Inhibitors From Sapodilla Plum Manilkara Zapota L., Sutthiduean Chunhakant
Chulalongkorn University Theses and Dissertations (Chula ETD)
Six different parts of Manilkara zapota which consisted of barks, flowers, fruits, leaves, roots and seeds were investigated for total phenolic content, total flavonoid content, antioxidant and antityrosinase activities. Methanol crude extract of flowers showed the highest total phenolic content (368.73 ± 0.65 mg GAE/g), while methanol crude extracts of seeds and roots showed high total flavonoid content (90.21 ± 0.57 and 89.03 ± 1.00 mg QE/g, respectively). Methanol crude extract of seeds showed the strongest DPPH (IC50 282.05 ± 0.60 μg/mL) and ABTS (IC50 205.11 ± 0.89 μg/mL) radical scavenging activities and showed the highest FRAP value of 296.46 …
Optimization Of D-Lactic Acid Production By Terrilactibacillus Laevilacticus Sk5-6 And Fermentation Process Scale Up In 30 Litre-Fermentor, Woraphot Toliang
Optimization Of D-Lactic Acid Production By Terrilactibacillus Laevilacticus Sk5-6 And Fermentation Process Scale Up In 30 Litre-Fermentor, Woraphot Toliang
Chulalongkorn University Theses and Dissertations (Chula ETD)
PLA, which is one of biodegradable plastic stereocomplex is made by block polymerization of optically pure L- and D-lactic acid. With stereoblock structure, heat and mechanical properties of PLA products can be improved. Thus, the demand of D-lactic acid has been increased. However, the market supply is still limited. In-house work reported that Terrilactibacillus laevilacticus SK5-6, the novel bacterium has been isolated from soil and later identified as the potent D-lactic acid producer. Moreover, it could produce high D-lactic acid from glucose with high optical purity in flask scale. To improve the fermentation performance, further process optimization was conducted in …
Malfunctioned Pacemaker And Business Operator's Liability In Us, Eu And Australia: Implication For Thailand, Peerasak Ounhachoke
Malfunctioned Pacemaker And Business Operator's Liability In Us, Eu And Australia: Implication For Thailand, Peerasak Ounhachoke
Chulalongkorn University Theses and Dissertations (Chula ETD)
At the present time, for the purpose of healthcare, pacemakers and other implantable medical devices are playing a significant role. However, the severity of level of damage arising from a malfunctioning pacemaker may be higher when compared with other simple products because when taking into consideration the characteristics and purpose of a pacemaker, it was normally implanted into a patient's body to control an abnormal heartbeat rate; therefore, a malfunctioned pacemaker may potentially cause harmful consequences, and in the worst scenario, death. From the abovementioned issue, the aspects of this research focused on the evolution of the laws and regulations …
Legal Measures For Employer To Reach Fair Practice In Organizational Restructuring In Thailand, Pitsanuchai Thongtha
Legal Measures For Employer To Reach Fair Practice In Organizational Restructuring In Thailand, Pitsanuchai Thongtha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Restructuring, a normal managerial task of entrepreneurship, can lift up an enterprises' competitiveness potential in business societies. Restructuring will affect to the rights of all people in the enterprise. Labor laws and regulations not only provide adequate protection for employees, but also promote the flexibility to the business sectors. The employment relationships are involved with the actions of three parties - employees, employers and the government - that must substantially cooperate in order to establish efficient labor regulations. Thai labor laws which relate to working condition adjustment and dismissal are obsolete. It provides too much power for the courts in …
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 …
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 …
Nanocomposite Membranes Incorporated With Graphene Oxide For Co2/Ch4 Separation, Nadia Norahim
Nanocomposite Membranes Incorporated With Graphene Oxide For Co2/Ch4 Separation, Nadia Norahim
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biogas is an alternative energy produced by anaerobic digestion of organic matter. Generally, raw biogas consists of methane (CH4), carbon dioxide (CO2), few amount of hydrogen sulfide (H2S) and traces of water vapor. Nowadays, upgrading raw biogas is required in order to achieve higher calorific value and meet fuel standard by removal of CO2. In this study, composite membranes of PEG 400/Pebax 1657 blended polymer with graphene oxide (GO) and amine functionalized graphene oxide (Fn-GO) were successfully developed for CO2/CH4 gas separation. The effects of graphene oxide, amine functionalized graphene oxide and PEG 400 additions on CO2/CH4 separation performance were …
Characteristics And Catalytic Properties Of Agli/Sio2 Catalysts On Different Silica Supports For Oxidative Dehydrogenation Of Ethanol To Acetaldehyde, Narawich Mukda
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work focuses on investigation of the oxidative dehydrogenation and non-oxidative dehydrogenation of ethanol over AgLi/SiO2 catalysts to produce acetaldehyde by having three different types of silica support, spherical silica particle (small particle size; SPS), medium silica particle size (MPS), and large silica particle size (LPS). The spherical silica particle (SSP) was synthesized using the sol-gel method, whereas SiO2 (MPS) and SiO2 (LPS) were obtained from commercial suppliers. AgLi/SiO2 catalysts were prepared by incipient wetness co-impregnation method. The physicochemical properties of catalysts were analyzed by using several technique such as X-ray diffraction (XRD), N2-physisorption, SEM-EDX, UV-visible spectroscopy, H2-TPR. Moreover, the …
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. …