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Full-Text Articles in Engineering
Biodiesel Production From Cooking Palm Oil In The Presence Of Cao/Γ-Al2o3 Catalyst Using Rotating Packed-Bed Reactor, Patcharaporn Sukjarern
Biodiesel Production From Cooking Palm Oil In The Presence Of Cao/Γ-Al2o3 Catalyst Using Rotating Packed-Bed Reactor, Patcharaporn Sukjarern
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis proposed the biodiesel production from cooking palm oil by using rotating pack bed reactor (RPB). The experiments were divided into 3 parts i) preparation of CaO/γ-Al2O3 catalyst and catalytic activity for the transesterification in a conventional mechanical stirrer reactor (MS). ii) study of CaO/γ-Al2O3 heterogeneous catalysts using RPB iii) study of NaOH homogeneous catalysts using RPB by packing inert packing bed. The Response surface methodology (RSM) based on the Central composite design (CCD) was used to reduce the number of experiments. The optimum condition for CaO /γ-Al2O3 catalyst preparation was at calcination temperature of 500ºC and 24%CaO/γ- Al2O3. …
Preparation Of Ba0.5sr0.5(Co0.8fe0.2)1-Xtaxo3-Δ Perovskite Anode For Solid Oxide Electrolysis Cell And Comparison Of Electrochemical Performance And Durability With The Basic Anodes, Patthiya Prasopchokkul
Preparation Of Ba0.5sr0.5(Co0.8fe0.2)1-Xtaxo3-Δ Perovskite Anode For Solid Oxide Electrolysis Cell And Comparison Of Electrochemical Performance And Durability With The Basic Anodes, Patthiya Prasopchokkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Among perovskite anodes in solid oxide electrolysis cell (SOEC), Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) has gained much attention due to its relatively high performance. However, the BSCF still suffers from chemical instability. In this study, partial substituting higher valance Ta5+ (5, 10, 15 and 20 mol%) at the B-site (Co2+/Fe3+) of BSCF was investigated to improve its structural stability. The Ba0.5Sr0.5(Co0.8Fe0.2)1-xTaxO3-δ (BSCFTax, 0 ≤ x ≤ 0.20) were synthesized by citrate-EDTA complexing method. The BSCF and BSCFTa0.05 exhibited the single phase perovskite while segregation of Ta2O5 and Ta3N5 were observed in other samples. The symmetrical half-cell having the yttria stabilized zirconia (YSZ) as …
Effect Of Titania Phase Composition In Wo3/Tio2 Catalysts On Catalytic Properties In Dehydration Of Ethanol To Diethyl Ether, Phatthraporn Termvoratham
Effect Of Titania Phase Composition In Wo3/Tio2 Catalysts On Catalytic Properties In Dehydration Of Ethanol To Diethyl Ether, Phatthraporn Termvoratham
Chulalongkorn University Theses and Dissertations (Chula ETD)
At the present, several agricultural products can be used as raw materials for bio-ethanol production and consequently converted it into many valuable substances such as ethylene and diethyl ether. This can undergo via WO3/TiO2 catalyst in which the anatase phase of titania usually has a better activity on ethanol dehydration to diethyl ether and ethylene than rutile phase. However, pure anatase phase of titania perhaps does not give the best of catalytic properties. So, this study investigates on the effects of tungsten on titania-supported catalysts with different phase composition of titania consisting of anatase and rutile phase with various proportion …
Ni Catalyst Supported On Open-Cell Ceramic Foam For Glycerol Steam Reforming, Phichamon Sookjitsumran
Ni Catalyst Supported On Open-Cell Ceramic Foam For Glycerol Steam Reforming, Phichamon Sookjitsumran
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work studied of nickel catalyst on open-cell ceramic foam for hydrogen production from glycerol steam reforming. Effect of different foam materials (alumina and zirconia), different pore density (PPI) at 10, 20 and 30 PPI and different feed flow rate (0.04, 0.2 and 0.4 ml/min) on physical and chemical properties and catalyst performance in fixed-bed reactor (16 mm diameter, 500 mm length and 20 mm catalyst bed) were investigated. Fresh and used catalysts were characterized by various techniques including XRD, SEM-EDX, H2-TPR, ICP, N2 adsorption-desorption, TPO and TGA. Catalyst performance was observed in glycerol steam reforming in condition as follows; …
Efficiency On Extending The Shelf-Life Of Ripened Mango (Cv. Golden Nam Dokmai) Using Bioplastic Bags From Laboratory Scale And Industrial Scale, Tanudkid Butweangphant
Efficiency On Extending The Shelf-Life Of Ripened Mango (Cv. Golden Nam Dokmai) Using Bioplastic Bags From Laboratory Scale And Industrial Scale, Tanudkid Butweangphant
Chulalongkorn University Theses and Dissertations (Chula ETD)
Efficiency in extending the shelf-life of ripened Golden Nam Dokmai by using bioplastic bags from laboratory scale and industrial scale production was tested. Polylactic acid (PLA) pellets and various fillers were mixed via twin screw extruder before being blown into film via extruder attached to blown film die in laboratory scale and industrial scale equipment. Oxygen and water vapor permeability of both kinds of bioplastic bags were evaluated for used as modified atmosphere packaging, for extend shelf-life of ripened mango. The oxygen permeability of films was 1,635.59±87.75 and 1,250.64±96.42 cc/m2-day and their water vapor permeability was 165.26±5.74 and 240.45±57.76 g/m2-day …
The Synthesis Of Hyperbranched Epoxy Resin For Improvement Of Thermal, Mechanical, And Adhesion Properties Of Epoxy Adhesive, Tossapol Boonlert-Uthai
The Synthesis Of Hyperbranched Epoxy Resin For Improvement Of Thermal, Mechanical, And Adhesion Properties Of Epoxy Adhesive, Tossapol Boonlert-Uthai
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to synthesize and characterize the hyperbranched epoxy resin synthesized by A2 + B4 polycondensation reaction consisting of bisphenol A (BPA) and polyethylene glycol (PEG) as A2 monomers, pentaerythritol as B4 branching monomer, and epoxide end group. There were varying PEG contents of 0, 5, 10, and 15 wt% of BPA. It was found that the synthesized resins could be confirmed by identifying the important chemical bond and possible structure by Fourier-transform infrared spectroscopy (FTIR) and H- and 13C-nuclear magnetic resonance (H-NMR and 13C-NMR) techniques. The 13C-NMR technique could identify the degree of branching (DB) of the synthesized …
Separation Of Trace Palladium Chloro Complexes From Wastewater Of Electroless Plating Process Via Hollow Fiber Supported Liquid Membrane, Vanee Mohdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The separation of palladium (Pd (II)) from wastewater containing copper (Cu (II)) and nickel (Ni (II)) is investigated via hollow fiber supported liquid membrane (HFSLM). The viability to separate Pd (II) was established by controlling the influence of operating conditions viz. aqueous feed acidity, carrier concentration, types of stripping solution as well as flows rate of feed and stripping solutions. A complete separation of Pd (II) acheiving >99% extraction and 87.09% recovery was demonstrated under optimum conditions of 6%(v/v) Aliquat 336, pH 2 as aqueous feed acidity, 0.5 M thiourea mixed with 0.1 M HCl as a strippant and 100 …
Non-Faradaic Electrochemical Modification Of Catalytic Activity (Nemca) Of Propane Oxidation On Pt/Ysz Thin Film Cell, Wanchana Lelalertsupakul
Non-Faradaic Electrochemical Modification Of Catalytic Activity (Nemca) Of Propane Oxidation On Pt/Ysz Thin Film Cell, Wanchana Lelalertsupakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, non-Faradaic Electrochemical Modification of Catalytic Activity (NEMCA) of propane oxidation over Pt/yttria-stabilized zirconia (YSZ) thin films on alumina substrates has been studied. YSZ thin films were initially prepared by slurry dip coating and calcined at a relatively lower temperature of 800 oC. Propane oxidation at temperatures in a range of 300-500 oC clearly exhibited NEMCA. The maximum rate enhancement ratio was close to 3 at an applied potential of 1.0 V and a reaction temperature of 400 oC. The maximum faradaic efficiency was higher than 10,000 at an applied potential of 0.2 V and 300oC. However, NEMCA …
One-Pot Conversion Of Furfural To G-Valerolactone Over Co- And Pt-Doped Zsm-5 Catalysts, Warucha Auppahad
One-Pot Conversion Of Furfural To G-Valerolactone Over Co- And Pt-Doped Zsm-5 Catalysts, Warucha Auppahad
Chulalongkorn University Theses and Dissertations (Chula ETD)
γ-Valerolactone (GVL) is one of the useful biomass compounds produced via different reaction pathways from hemicellulose. Typically, GVL is produced by conversion of furfural using supported metal catalysts. In this study, Co- and Pt-doped /ZSM-5 catalysts with Co loadings (0-10 wt%) and Pt loadings (0.5-2 wt%) were prepared by impregnation method and employed in the one-pot conversion of furfural to GVL. The reactions were carried out in a 100 cm3 batch stainless steel reactor at 120 oC atmospheric pressure for 5 h. The products were analysed by gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). The major products were GVL, …
Performance Analysis Of The Proton-Conducting Solid Oxide Electrolysis Cell Coupling With Dry Methane Reforming, Wissawa Chalee
Performance Analysis Of The Proton-Conducting Solid Oxide Electrolysis Cell Coupling With Dry Methane Reforming, Wissawa Chalee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The proton-conducting solid oxide electrolysis cell (H-SOEC) is a clean technology for syngas production from H2O and CO2 through electrochemical and chemical reactions. However, it gives low CO2 conversion and produces syngas product with high H2O content. Therefore, the H-SOEC coupling with a dry methane reforming process (H-SOEC/DMR) is proposed to improve its performance. The process flowsheet of the H-SOEC/DMR is developed by using Aspen Plus and used to evaluate the performance of H-SOEC/DMR. The performance analysis of the H-SOEC/DMR shows that under the temperature range of 1073-1273 K, the %CO2 and %CH4 conversions of higher than 90% and 80% …
Development Of Nickel Alloy Hydrogen Electrodes For Solid Oxide Electrolysis Cell, Aritat Wongmaek
Development Of Nickel Alloy Hydrogen Electrodes For Solid Oxide Electrolysis Cell, Aritat Wongmaek
Chulalongkorn University Theses and Dissertations (Chula ETD)
The conventional nickel-yttrium stabilized zirconia (Ni-YSZ) cathode in solid oxide electrolysis cell (SOEC) suffers from oxidation after exposed to steam during electrolysis for hydrogen production. The Ni-chromium (Cr)-iron (Fe) alloys with various compositions are introduced to improve cathode oxidation resistance. This study aims to study the effect of alloy contents and determine suitable fabrication method for SOEC cathode. The alloy containing cathode should satisfy both high electrochemical performance and low degradation rate. The content of Fe and Cr are varied in the range of 0-20%wt when the weight ratio of metal to YSZ is maintained constantly at 60:40. The SOEC …
Correlation Development Of Wax Deposition Prediction From Fang Oil Field, Aung Thwin Thu Aye
Correlation Development Of Wax Deposition Prediction From Fang Oil Field, Aung Thwin Thu Aye
Chulalongkorn University Theses and Dissertations (Chula ETD)
In petroleum industry, wax deposition is a critical operational challenge. It occurs in various locations in the petroleum production chain including well tubing. Hexane, chemical inhibitor, is used to prevent the wax problem of oil from Fang oilfield by the measurement of pour point, wax appearance temperature (WAT) and wax deposition. An increasing shear rate can reduce WAT and the deposited amount increases with lowering the temperature in Fang crude oil. Moreover, the non-linear regression analysis of Fang crude oil with and without hexane in different conditions are done for all three tests. Those regression analysis equations can predict WAT …
Pre-Feasibility Study Of Improving Quality Of Low-Grade Fluorite. A Case Study At Phanomthuan Deposit, Kanchanaburi, Thailand, Keosaychai Souvannavong
Pre-Feasibility Study Of Improving Quality Of Low-Grade Fluorite. A Case Study At Phanomthuan Deposit, Kanchanaburi, Thailand, Keosaychai Souvannavong
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study was presented the pre-feasibility study of improving quality of low-grade fluorite from Phanomthuan deposit, Kanchanaburi province, Thailand. The purpose of this study aims to explore the optimal condition in order to remove the impurities which contained high SiO2, CaCO3 and other minerals, also evaluate the project in term of economic. Therefore, the improvement quality of fluorite by using froth flotation techniques was reach the ceramic grade. The raw material characterization contains CaF2 = 29.4 Wt.%, SiO2 = 43.9 Wt.% and CaCO3 = 6.9 Wt.%. After flotation process the optimal condition result which contains CaF2 = 96.46 Wt.%, …
Geomechanical Modeling Of Salt Cavern Stability For Carbon Dioxide Storage In The Maha Arakham Formation, Northeastern Thailand, Narumas Pajonpai
Geomechanical Modeling Of Salt Cavern Stability For Carbon Dioxide Storage In The Maha Arakham Formation, Northeastern Thailand, Narumas Pajonpai
Chulalongkorn University Theses and Dissertations (Chula ETD)
In Thailand, CO2 emissions quadrupled over the past three decades since 1989, with the power generation sector as the main contributor by burning fossil fuels to produce electricity. Therefore, the power generating industry has come under scrutiny and been pressed by society to take responsibility. Carbon Capture and Storage (CCS) is one of the many methods to deal with CO2 emissions. Generally, CO2 is captured and stored in geological formations, e.g. rock salt deposits. Salt caverns have been intensively studied regarding their usage for CO2 storage because of their favourable characteristics. In this research, the Finite Element Method (FEM, ANSYS …
The Production Of Bio-Jet Fuel From Palm Fatty Acid Distiliate Over Covalt And Nickel Supported Hzsm-12 Catalysts, Ariya Eka Alel
The Production Of Bio-Jet Fuel From Palm Fatty Acid Distiliate Over Covalt And Nickel Supported Hzsm-12 Catalysts, Ariya Eka Alel
Chulalongkorn University Theses and Dissertations (Chula ETD)
Aviation sector becomes one of the largest-developing public transportation nowadays, the number of air passangers always increases year by year. However, this number are proportionally related to the enhance of jet-fuel worldwide demand. The conventional jet-fuel are commonly known as a carbon dioxde emission source and the world has more concern to this pollutant due to its contribution to the climate change. The usage of renewable materials to produce jet fuel is more glanced. One of the renewable sources can be used to generate green jet fuel is palm fatty acid distillate (PFAD) which is a by-product of palm oil …
Natural Gas Storage Using Clathrate Technology : Enhanced Formation At High Temperature, Kan Jeenmuang
Natural Gas Storage Using Clathrate Technology : Enhanced Formation At High Temperature, Kan Jeenmuang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Solidified natural gas (SNG) by storing natural gas in the hydrate form, which is safe and easy to recover stored gas compared to other methods. However, to make this technology competitive, storing natural gas at a higher temperature, lower pressure with faster formation is needed. Tetrahydrofuran (THF) is a well-known thermodynamic promoter used to increase the hydrate formation temperature. However, increasing the hydrate formation temperature has a drawback on decreasing the formation rate. Nonpolar amino acids have been used as a secondary promoter, which increases the hydrate formation kinetics. This work used 5.56 mol% THF cooperated with different concentrations of …
Silver Nano Polymer Composite Membrane For Hydrogen Sulfide Sensing, Muhammad Bagus Arif
Silver Nano Polymer Composite Membrane For Hydrogen Sulfide Sensing, Muhammad Bagus Arif
Chulalongkorn University Theses and Dissertations (Chula ETD)
Optical and electrochemical sensor for H2S sensing were developed using silver nanoparticles (AgNPs) immobilized onto polyelectrolyte membranes (PEMs) as substrate. Two approach for the deposition of the silver nanoparticles namely in-situ and ex-situ were compared for their sensing efficiency. The Poly(diallyldimethylchloride) (PDADMAC) and Poly(sodium styrenesulfonate) (PSS) were used to build PEMs via layer-by-layer assembly mechanism as polycation and polyanion respectively. In situ synthesis of silver nanoparticles was achieved by dipping the PEM coated substrate in silver nitrate (AgNO₃) solution followed by sodium borohydride (NaBH₄) as reducing agent. For ex situ technique, a monolayer of pre-synthesized silver nanoparticles was deposited as …