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,
2019
Faculty of Engineering
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 …
Study Effect Of Catalyst Shape On The Ethylbenzene Dehydrogenation In Fixed Bed Reactor By Using Various Mathematical Models,
2019
Faculty of Engineering
Study Effect Of Catalyst Shape On The Ethylbenzene Dehydrogenation In Fixed Bed Reactor By Using Various Mathematical Models, Pawinee Maithong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, the chemicals are mostly manufactured by catalytic reactions in fixed bed reactor. Catalyst shape affects to reactor performance and the effect is studied by mathematic models which are varied forms to more realistic. Therefore, the objective of research is to study the effect of catalyst shape on the behavior of reactor for ethylbenzene dehydrogenation to styrene in gas phase by varied form. The simplest model, pseudohomogeneous model (model1), predicts 36.52% ethylbenzene conversion. The more complex model, heterogeneous model accounting for internal mass transfer (model2), predicts 34.49% conversion that equals to the model accounting for internal mass and heat transfer(model3). …
Effect Of Titania Phase Composition In Wo3/Tio2 Catalysts On Catalytic Properties In Dehydration Of Ethanol To Diethyl Ether,
2019
Faculty of Engineering
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,
2019
Faculty of Engineering
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; …
Solid Acid Catalyst Prepared Via One Step Hydrothermal Carbonization For Production Of 5-Hydroxymethylfurfural In Biphasic System,
2019
Faculty of Engineering
Solid Acid Catalyst Prepared Via One Step Hydrothermal Carbonization For Production Of 5-Hydroxymethylfurfural In Biphasic System, Phornwimol Siabbamrung
Chulalongkorn University Theses and Dissertations (Chula ETD)
As one of the most important precursor for various high-value chemicals, 5-hydroxymethylfurfural (HMF) is a biomass-derived compound that has gained increasing chemical research and industrial interests in recent years. In this study, production of HMF from direct dehydration of glucose was investigated with various types of catalysts prepared by a modified one-step HTC method. Two type of acids were employed for the functionalization of the catalyst, namely, 2-Hydroxyethylsulfonic acid (C2H6O4S) and Hydrochloric acid (HCl), making C-SO3H and C-HCl catalysts. Moreover, both of them were synthesized by adding acrylic acid to the C-SO3H-A and C-HCl-A catalysts. Their physicochemical characteristics and catalytic …
Efficiency On Extending The Shelf-Life Of Ripened Mango (Cv. Golden Nam Dokmai) Using Bioplastic Bags From Laboratory Scale And Industrial Scale,
2019
Faculty of Engineering
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 …
Modeling Production Of Aromatic From N-Paraffins With Chemical Equilibria,
2019
Faculty of Engineering
Modeling Production Of Aromatic From N-Paraffins With Chemical Equilibria, Thidarat Detsut
Chulalongkorn University Theses and Dissertations (Chula ETD)
Chemical Equilibrium models were constructed for modeling and developing the aromatic production model from the normal paraffin at the equilibrium of the reaction with catalysts, i.e. ZSM-5(80) and Mo2C. The models were verified under operating temperatures of 450-500 ° C under atmospheric pressure at 1 atm. By examining the accuracy by comparing the data calculated from each model with the value obtained from the corresponding experiments at the condition that the reaction is balanced. The suitable equilibrium model depends on the type of catalyst used in the system. The accuracy of all equilibrium models could be improved by specifying the …
The Synthesis Of Hyperbranched Epoxy Resin For Improvement Of Thermal, Mechanical, And Adhesion Properties Of Epoxy Adhesive,
2019
Faculty of Engineering
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,
2019
Faculty of Engineering
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,
2019
Faculty of Engineering
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 …
Synthesis Of Ziegler-Natta Catalysts Containing Sicl4/Teos/Ticl4/Mgcl2 For Ethylene/1-Hexene Copolymerization,
2019
Faculty of Engineering
Synthesis Of Ziegler-Natta Catalysts Containing Sicl4/Teos/Ticl4/Mgcl2 For Ethylene/1-Hexene Copolymerization, Wasinee Ousirisombat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polyethylene (PE) is still worldwide manufacturing, and its most productivity is in Asia. The main categories of PE including high density polyethylene (HDPE), low density polyethylene (LDPE) and linear low density polyethylene (LLDPE). Ziegler-Natta catalyst is catalyst that used for α-olefins polymerization and it is widely used in industry because it has good activity with low operating cost. This research studies on synthesized SiCl4/TEOS/TiCl4/MgCl2 Ziegler-Natta catalyst in ethylene/1-hexene copolymerization with added silicon compounds,including tetraethylorthosilicate (TEOS) and SiCl4, used as additive in catalyst by varying 1-hexene comonomer at 0%, 3% and 5%. This research is separated into 2 parts, the first …
Performance Analysis Of The Proton-Conducting Solid Oxide Electrolysis Cell Coupling With Dry Methane Reforming,
2019
Faculty of Engineering
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,
2019
Faculty of Engineering
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 …
Electro-Deposited Polyaniline On Tio2 As A Photoanode For Improved Photoelectrochemical Performance In Water Oxidation And Methylene Blue,
2019
Faculty of Engineering
Electro-Deposited Polyaniline On Tio2 As A Photoanode For Improved Photoelectrochemical Performance In Water Oxidation And Methylene Blue, Reeda Jamsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polyaniline (PANI) deposited on TiO2 as a photoanode has been synthesized by the electro-polymerization method. The electrodeposition was performed in aqueous solutions containing 0.5 M aniline and 1 M H2SO4 at a constant current density. The photoanode demonstrated its potential applications for photocatalytic degradation of methylene blue dye (MB) and photoelectrochemical (PEC) water splitting. A ~2.7 fold enhancement in the photodegradation activity at 0.9V vs. Ag/AgCl of a bias voltage and the high water oxidation photocurrent density of PANI/TiO2 on FTO photoanode achieves 1.3 mA cm-2 at 0.6V vs. Ag/AgCl under illumination which is higher than that pure TiO2 on …
กัมมันตภาพและเสถียรภาพของ Ptiro2 รองรับด้วยท่อนาโนคาร์บอนที่หุ้มพอลิแอนิลีนสำหรับเซลล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้,
2019
คณะวิทยาศาสตร์
กัมมันตภาพและเสถียรภาพของ Ptiro2 รองรับด้วยท่อนาโนคาร์บอนที่หุ้มพอลิแอนิลีนสำหรับเซลล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้, ลดาวรรณ์ ธูปชัย
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้เป็นการศึกษาผลของตัวรองรับต่อกัมมันตภาพและเสถียรภาพของตัวเร่งปฏิกิริยาแพลทินัมอิริเดียมออกไซด์ในเซลล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้ ตัวรองรับที่ใช้ในการทดสอบ ได้แก่ คาร์บอนวัลแคน (C) ท่อนาโนคาร์บอน (CNTs) และท่อนาโนคาร์บอนที่หุ้มพอลิแอนิลีน (CNTs-PANI) พบว่าตัวเร่งปฏิกิริยา PtIrO2/CNTs-PANI มีกัมมันตภาพในการเร่งปฏิกิริยามากที่สุดทั้งในปฏิกิริยารีดักชันของออกซิเจนและปฏิกิริยาการเกิดออกซิเจน โดยความหนาแน่นเชิงจลนพลศาสตร์สำหรับปฏิกิริยารีดักชันของออกซิเจน ที่ 0.6 โวลต์เทียบกับศักย์ไฟฟ้ามาตรฐานคาโลเมล เท่ากับ 1.24 มิลลิแอมแปร์ต่อตารางเซนติเมตร และปฏิกิริยาการเกิดออกซิเจน ที่ 1.55 โวลต์เทียบกับศักย์ไฟฟ้ามาตรฐานคาโลเมล เท่ากับ 41.36 มิลลิแอมแปร์ต่อตารางเซนติเมตร หลังผ่านการทดสอบเสถียรภาพในสารละลายกรดซัลฟิวริก จำนวน 1000 รอบ พบว่าตัวเร่งปฏิกิริยา PtIrO2/CNTs-PANI มีการลดลงของความหนาแน่นกระแสไฟฟ้าและอัตราการลดลงของพื้นที่ผิวในการเกิดปฏิกิริยาน้อยที่สุด ทั้งในปฏิกิริยารีดักชันของออกซิเจนและปฏิกิริยาการเกิดออกซิเจน เนื่องจากพอลิแอนิลีนที่เติมลงไปช่วยในการยึดเกาะระหว่างตัวเร่งปฏิกิริยาและตัวรองรับ ทำให้ตัวเร่งปฏิกิริยากระจายตัวได้ดีและมีเสถียรภาพ จากผลการทดลองข้างต้น พบว่าตัวเร่งปฏิกิริยา PtIrO2/CNTs-PANI เหมาะสมสำหรับการเร่งปฏิกิริยาทั้งในปฏิกิริยารีดักชันของออกซิเจนและปฏิกิริยาการเกิดออกซิเจน เพื่อใช้เป็นตัวเร่งปฏิกิริยาแบบสองหน้าที่สำหรับเซล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้
Effects Of Titanium Content In Ziegler-Natta Catalyst On The Reducibility Of Triethylaluminum Cocatalyst,
2019
Faculty of Engineering
Effects Of Titanium Content In Ziegler-Natta Catalyst On The Reducibility Of Triethylaluminum Cocatalyst, Pichayapong Sitthijun
Chulalongkorn University Theses and Dissertations (Chula ETD)
The Ziegler-Natta catalytic system for olefin polymerization comprises the TiCl4 precursor adsorbed on MgCl2 support and reacted with an alkylating agent to generate active sites. The reduction of TiCl4 valence plays a crucial role in the formation of Ti3+ and Ti2+ active species for ethylene polymerization whereas only Ti3+ active for propylene polymerization. Thus, the reducibility of Ti-based catalyst using AlEt3 cocatalyst was studied during ethylene and propylene polymerization which has not been previously studied yet. For this study, the effect of Ti content on the reducibility was considered through the changing of catalytic activity with the increase of AlEt3 …
Roles Of Wox On Pt/Γ-Al2o3 Catalysts On The Prevention Of Pt Metal Sintering During Hydrogenolysis Of Glycerol To 1,3-Propanediol,
2019
Faculty of Engineering
Roles Of Wox On Pt/Γ-Al2o3 Catalysts On The Prevention Of Pt Metal Sintering During Hydrogenolysis Of Glycerol To 1,3-Propanediol, Poonnapa Limsoonthakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hydrogenolysis of glycerol to produce 1,3-propanediol is the most effective reaction which conversing excess glycerol from biodiesel production to high-value-add product ; especially, 1,3-propanediol. A solid catalyst which generally used as selective to 1,3-propanediol production is Pt-based catalyst with γ-Al2O3 supporter which was prepared by wet impregnation method in this study. Although hydrogenolysis of glycerol reaction has been carried out under mild conditions: 140 °C and 5 bar of initial H2 pressure, the deactivation of non-reduced Pt/γ-Al2O3 catalyst is observed. To investigate the deactivation of the catalyst, the used Pt/γ-Al2O3 and Pt/WOx/γ-Al2O3 catalysts were characterized by N2-physisorption, ICP-OES, SEM-EDX, XRD, …
Selective Oxidation Of H2s In Biogas To Sulfur On V2o5 Catalyst Dispersedon Ceo2-Mo2 (M = Ti, Si, Zr) Mixed Oxides,
2019
Faculty of Engineering
Selective Oxidation Of H2s In Biogas To Sulfur On V2o5 Catalyst Dispersedon Ceo2-Mo2 (M = Ti, Si, Zr) Mixed Oxides, Benjamaporn Tudkesorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the characteristics and catalytic performances of V2O5catalysts supported on mixed oxides CeO2-MO2 (M = Ti, Si, Zr) as compared to the commercial CeO2 supported ones were studied in the selective catalytic oxidation of H2S in biogas to sulfur at 130oC. The mixed-oxide supports were prepared by co-precipitation method with 3 wt.% vanadium loading by wet impregnation method. From the XRD and Raman spectroscopy results, all the catalysts exhibited high dispersion of V2O5 on the supports with the 1:1 molar ratio CeO2-SiO2 mixed oxide showed the highest conversion of H2S at ̴ 73% and low selectivity of SO2 …
Influences Of Cations And Anions In Aqueous Electrolyte On The Electrochemical Reduction Of Co2 Over Cu-Based Electrode,
2019
Faculty of Engineering
Influences Of Cations And Anions In Aqueous Electrolyte On The Electrochemical Reduction Of Co2 Over Cu-Based Electrode, Siraphat Somchit
Chulalongkorn University Theses and Dissertations (Chula ETD)
In present work, various aqueous electrolyte solution including Na2SO4, NaCl, NaHCO3, K2SO4, KCl, KHCO3, Cs2SO4, CsCl, and CsHCO3 were employed in the CO2-ER using Cu-based electrode in an H-cell type reactor. The effects of cations and anions on the production rate were analyzed by GC and NMR. The results showed that electrolyte containing Cl- as anion not only facilitated CO2-ER but also suppressed H2 evolution, the competitive reaction. For the cations effect, rate of CO/H2 production increased with increasing cation size (Na+ < K+ < Cs+). The mixture of HCO3- and Cl- with various ratios (1:1, 1:2, 1:3, and 1:4) were also investigated. It was found that mixed electrolytes can improve the performance of electrolyte. The more Cl- concentration (0.4M) in mixed electrolyte, the Cu-Cl catalytic film can be presented, which electron transfer is promoted and intermediates can diffuse easier, resulting in the formation of C2 products. Furthermore, the applied potential in the range of -1.2V to -2.0V vs. Ag/AgCl on CO2-ER were studied. At higher applied potential, CO intermediates can be further reduced to C2 products. The electrolyte performances were correlated to the reduction current and resistance of charge transfer (Rct) as revealed by linear sweep voltammetry and electrochemical impedance spectroscopy results, respectively.
Correlation Development Of Wax Deposition Prediction From Fang Oil Field,
2019
Faculty of Engineering
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 …
