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Full-Text Articles in Chemical Engineering
Development Of Silica-Based Support Material From Sugarcane Bagasse Ash For Synthesis Of Carbon Nanotubes, Maturada Assawagetmanee
Development Of Silica-Based Support Material From Sugarcane Bagasse Ash For Synthesis Of Carbon Nanotubes, Maturada Assawagetmanee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Sugarcane bagasse ash (SCBA), an abundant agricultural residue, is converted into high-value silica powder through a novel route involving calcination and acid leaching. This transformative process not only valorizes waste biomass but also yields silica nanoparticles with tailored microstructural properties suitable for application in carbon nanotube (CNT) production. The resultant silica powder was utilized as a catalyst support impregnated with Fe nanocatalyst for synthesizing CNTs from benzene. The effective route with a process sequence of 1 M HCl acid leaching followed by calcination could provide silica powder with a specific surface area of 12.29 m2/g, which could accommodate Fe nanocatalyst …
Development Of Calcium Oxide Sorbent From Waste Natural Materials For Co2 Capture, Muhammad Dody Isnaini
Development Of Calcium Oxide Sorbent From Waste Natural Materials For Co2 Capture, Muhammad Dody Isnaini
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aims to develop calcium oxide (CaO) sorbents for carbon oxide (CO2) capture by using various waste natural materials: eggshells, crab shells, and green mussel shells. These natural materials were used as precursors for the synthesis of CaO sorbents using the citric acid-assisted sol-gel method. Various characterization techniques, including N2 physisorption, XRD, XRF, CO2-TPD, TG/DTG, and FE-SEM, were performed to assess the physicochemical and thermal properties of the synthesized sorbents. The sorbent is investigated for its CO2 adsorption and recycle ability, as it has been a major issue for large-scale deployment of cyclic CO2 capture technology. This study also …
Investigation Of Molecular Interactions In Electrocatalysis Using Atomic Force Microscopy, Parivat Phiphatbunyabhorn
Investigation Of Molecular Interactions In Electrocatalysis Using Atomic Force Microscopy, Parivat Phiphatbunyabhorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Electrocatalysis at the nanoscale is fundamentally governed by molecular interactions, but these processes remain poorly understood due to their difficulty to directly investigate and their complex nature. In this study, atomic force microscopy (AFM)-based force spectroscopy is employed to investigate interfacial forces and reactivity in two representative systems: the electrochemical deterioration and healing of Au nanothin films on n-type silicon and the electrocatalytic reduction of MEA-CO2 adduct on Cu electrocatalysts. In the Au nanothin film system, observing that surface degradation is mediated by anionic cluster interactions and modulated by intrinsic band bending and surface energy effects. Remarkably, 20-nm Au films …
Design And Multi-Objective Optimization Of Methanol Reforming, High-Temperature Proton Exchange Membrane Fuel Cell And Organic Rankine Cycle Integrated System, Supawat Taweekayujan
Design And Multi-Objective Optimization Of Methanol Reforming, High-Temperature Proton Exchange Membrane Fuel Cell And Organic Rankine Cycle Integrated System, Supawat Taweekayujan
Chulalongkorn University Theses and Dissertations (Chula ETD)
The growing demand for electricity across all sectors has led researchers to focus on developing advanced electric generation technologies that offer high performance and are environmentally friendly. This study presents the design and multi-objective optimization of an integrated system combining sorption-enhanced chemical looping reforming of methanol (SECL-OSRM), high-temperature proton exchange membrane fuel cells (HT-PEMFCs), and a Recuperative-Regenerative Organic Rankine Cycle (RR-ORC). The hybrid system was simulated using Aspen Plus, focusing on energy, exergy, and exergoeconomic analyses. Sensitivity analyses of SECL-OSRM and ORC subsystems were performed to identify optimal operating conditions and working fluids. A Box-Behnken design of experiments approach generated …
Uv-Vulcanized Natural Rubber Grafted With Methyl Methacrylate For Production Of Ultrafine Fully Vulcanized Natural Rubber Powder, Torntawat Kiratiphongwut
Uv-Vulcanized Natural Rubber Grafted With Methyl Methacrylate For Production Of Ultrafine Fully Vulcanized Natural Rubber Powder, Torntawat Kiratiphongwut
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to develop ultrafine fully vulcanized powdered natural rubbers (UFPNRs). The preparation process began with grafting methyl methacrylate (MMA) monomers onto natural rubber particles, followed by UV irradiation using an acrylate-based coagent and a photoinitiator. The final product was dried using a spray-drying technique. The successful grafting of MMA onto the natural rubber particles was confirmed using Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). At a monomer concentration of 15 parts per hundred parts of dry rubber weight (phr), the highest grafting efficiency of 89 ± 0.7% was achieved. The research investigated the use of acrylate …
Molecular Dynamics Investigation Of Fluorine-Free Electrolytes For Sodium-Ion Batteries, Phitchapa Ausamanwet Zijdemans
Molecular Dynamics Investigation Of Fluorine-Free Electrolytes For Sodium-Ion Batteries, Phitchapa Ausamanwet Zijdemans
Chulalongkorn University Theses and Dissertations (Chula ETD)
Sodium-ion batteries (SIBs) are a promising alternative to lithium-ion batteries due to the abundance and low cost of sodium. However, conventional SIB electrolytes often rely on fluorine-based salts, contributing to the formation of persistent and environmentally harmful per- and polyfluoroalkyl substances (PFAs). This study employs molecular dynamics (MD) simulations to investigates the properties of fluorine-free electrolytes for SIBs, focusing on the solvation structure and dynamics of sodium ions (Na+) in bulk electrolytes and at the inner solid electrolyte interphase (SEI) for SIBs. Sodium perchlorate (NaClO4) at a concentration of 1 M was examined in glyme solvents with varying chain lengths, …
Electrochemical Regeneration Of Spent Monoethanolamine Solution After Carbon Dioxide Capture And Mineralization By Calcium Sulfate Addition, Nathaporn Kenbubpha
Electrochemical Regeneration Of Spent Monoethanolamine Solution After Carbon Dioxide Capture And Mineralization By Calcium Sulfate Addition, Nathaporn Kenbubpha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Carbon dioxide (CO2) is widely recognized as the primary greenhouse gas (GHG) driving global warming. Since the onset of the Industrial Revolution around 1850, the average atmospheric concentration of CO2 has steadily increased, reaching approximately 426 ppm as of March 2025. As a result, Carbon Capture, Utilization, and Storage (CCUS) has become a critical approach to mitigate this issue. Monoethanolamine (MEA) solution is widely used in various industries to capture CO2; however, the regeneration of MEA remains a challenge due to the high energy demands associated with the conventional stripping method, which requires boiling the solution. This study successfully developed …
การวิเคราะห์เปรียบเทียบแบบจำลองแบบดั้งเดิม แบบจำลองการเรียนรู้ของเครื่อง และแบบจำลองผสมสำหรับการทำนายสภาวะการทำงานของหอกลั่นเพนเทน-เฮกเซนที่มีจำนวนข้อมูลจำกัด, จิรภัทร ร่มแก้ว
Chulalongkorn University Theses and Dissertations (Chula ETD)
กระบวนการกลั่นเป็นกระบวนการที่นิยมใช้เป็นอย่างมากในอุตสาหกรรมเคมีซึ่งเป็นกระบวนการที่ใช้ค่าดำเนินการสูง การปรับสภาวะการดำเนินการของหอกลั่นสามารถช่วยให้ลดค่าดำเนินการที่ใช้ได้ แบบจำลองโดยการเรียนรู้ของเครื่อง (Machine learning model) สามารถนำมาใช้ในการช่วยเลือกสภาวะการดำเนินการได้และมีการนำมาประยุกต์ใช้ในสายงานวิศวกรรมเคมีอย่างแพร่หลายแต่กลับยังไม่มีการศึกษาถึงอัลกอริทึมของแบบจำลองที่เหมาะสมกับหอกลั่นรวมถึงจำนวนข้อมูลขั้นต่ำที่จำเป็นต้องใช้ในการสร้างแบบจำลอง วิทยานิพนธ์ฉบับนี้มีจุดประสงค์เพื่อศึกษาช่องว่างดังกล่าวและผลของการผสมข้อมูลระหว่างข้อมูลจริงกับข้อมูลสร้างที่ถูกสร้างขึ้นโดยแบบจำลองแบบดั้งเดิม (Conventional model) โดยใช้หอกลั่นแยกเพนเทนและเฮกเซนเป็นข้อมูล มีการเปรียบเทียบกับแบบจำลองแบบดั้งเดิมผ่านโปรแกรมที่นิยมใช้เพื่อเป็นเกณฑ์ในการตัดสินความน่าเชื่อถือของแบบจำลองโดยการเรียนรู้ของเครื่อง อัลกอริทึมที่นำมาศึกษามีด้วยกันสี่อัลกอริทึมได้แก่ การถดถอยแบบเคอร์เนล ริดจ์ (Kernel ridge regression) เคเนียร์เรสเนเบอร์ (k-Nearest neighbor) ต้นไม้การตัดสินใจ (Decision tree) และโครงข่ายประสาทเทียม (Artificial neural network) อัลกอริทึมที่เหมาะสมกับชุดข้อมูลหอกลั่นมากที่สุดคือโครงข่ายประสาทเทียมซึ่งมีความซับซ้อนในแบบจำลองมากที่สุดทำให้สามารถเรียนรู้ความสัมพันธ์ระหว่างตัวแปรในข้อมูลหอกลั่นได้โดยความแม่นยำจะเพิ่มขึ้นตามจำนวนข้อมูลฝึกที่ใช้ เมื่อนำข้อมูลสร้างที่มีความแม่นยำใกล้เคียงกับข้อมูลจริงผสมกับข้อมูลจริงจะสามารถเพิ่มความแม่นยำของแบบจำลองโดยการเรียนรู้ของเครื่องในกรณีที่มีจำนวนข้อมูลจริงน้อยได้
การวิเคราะห์เชิงเศรษฐศาสตร์เทคโนโลยีของแนวทางการผลิตไฮโดรเจนสำหรับกระบวนการเปลี่ยนคาร์บอนไดออกไซด์เป็นเมทานอลและเปลี่ยนเมทานอลเป็นโอลิฟินส์, กันตภณ มานิมนต์
การวิเคราะห์เชิงเศรษฐศาสตร์เทคโนโลยีของแนวทางการผลิตไฮโดรเจนสำหรับกระบวนการเปลี่ยนคาร์บอนไดออกไซด์เป็นเมทานอลและเปลี่ยนเมทานอลเป็นโอลิฟินส์, กันตภณ มานิมนต์
Chulalongkorn University Theses and Dissertations (Chula ETD)
อุตสาหกรรมปิโตรเคมีเป็นหนึ่งในแหล่งปล่อยก๊าซคาร์บอนไดออกไซด์ (CO2) คิดเป็นสัดส่วนใหญ่ของโลก โดยเฉพาะจากกระบวนการแครกเกอร์แนฟทาด้วยไอน้ำ (Steam Naphtha Cracking) การดักจับและใช้ประโยชน์จากคาร์บอน (Carbon Capture and Utilization: CCU) จึงเป็นแนวทางที่ได้รับความสนใจเพื่อลดการปล่อย CO2 หนึ่งในกระบวนการที่มีศักยภาพคือ ไฮโดรเจนของคาร์บอนไดออกไซด์ (Hydrogenation of CO2) เพื่อผลิตเมทานอล ซึ่งเมทานอลสามารถนำไปใช้เป็นวัตถุดิบในกระบวนการแปรรูปเป็นโอเลฟินส์ (Methanol-to-Olefins: MTO) ได้อีกด้วย งานวิจัยนี้ศึกษาแนวทางการผลิตไฮโดรเจนซึ่งเป็นสารตั้งต้นที่สำคัญของกระบวนการ โดยศึกษา3 ประเภท ได้แก่ ไฮโดรเจนสีเทา (Grey Hydrogen) จากกระบวนการ Steam Methane Reforming (SMR), Autothermal Reforming (ATR) และ SMR ร่วมกับ ATR, ไฮโดรเจนสีน้ำเงิน (Blue Hydrogen) และไฮโดรเจนสีเขียว (Green Hydrogen) จากกระบวนการอิเล็กโทรไลซิส (AEL) โดยทำการจำลองกระบวนการด้วย Aspen Plus และประเมินค่าเชิงเศรษฐศาสตร์ด้วยค่า LCOH (Levelized Cost of Hydrogen) ผลการศึกษาแสดงให้เห็นว่า ไฮโดรเจนสีเทาแบบ SMR มี LCOH ต่ำที่สุดที่ 1.03 USD/kg H2 แต่ปล่อย CO2 สูงสุด 13.44 kg CO2/kg H2 ขณะที่ไฮโดรเจนสีน้ำเงินให้การลด CO2 ที่ดีขึ้น 6.85 kg CO2/kg H2 ด้วยต้นทุนที่เพิ่มขึ้น 1.16 USD/kg H2 ส่วนไฮโดรเจนสีเขียวปล่อย CO2 ต่ำที่สุดแต่มีต้นทุนสูงสุดที่ 4.38 USD/kg H2 ดังนั้นการเลือกใช้แหล่งผลิตไฮโดรเจนที่เหมาะสมจึงมีผลโดยตรงต่อประสิทธิภาพและความยั่งยืนของกระบวนการผลิตเมทานอลและโอเลฟินส์ในอนาคต
Process Optimization Of Bioactive Compound Extraction From Aloe Vera Leaf Skin Using Natural Deep Eutectic Solvents: An Integrated Computational-Experimental Approach, Sopita Chanmee
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aimed to evaluate the efficiency of environmentally friendly natural eutectic solvents (NADESs) for the extraction of bioactive compounds from Aloe vera leaf skin (AVLS) in comparison with conventional solvents, namely water and 80% ethanol. The experiment used NADES based on choline chloride with four hydrogen bonding agents (HBDs), namely xylose, glycerol, propylene glycol and lactic acid. The results showed that ChCl:Xy gave the highest phenolic compounds content, while ChCl:La gave the highest anthraquinone content and antioxidant activity as tested by DPPH and FRAP. COSMO-RS and sigma profile analyses revealed the molecular interactions affecting the extraction efficiency, which showed …
Photocatalytic Efficiency Of Graphene Quantum Dots Incorporated With Tio2 Under Visible Light For Degradation Of Organic Dye, Ilada Sanprasert
Photocatalytic Efficiency Of Graphene Quantum Dots Incorporated With Tio2 Under Visible Light For Degradation Of Organic Dye, Ilada Sanprasert
Chulalongkorn University Theses and Dissertations (Chula ETD)
The rapid industrialization and increased use of organic dyes for production in many industries have led to extensive environmental pollution concerns. At present, photocatalytic dye degradation is an outstanding environmentally friendly process for removal and treatment of organic dyes from water pollutants that cause no harm to the environment. In this research, we investigated the performance of different crystallographic structure of TiO2 (anatase, rutile, and mixed anatase/rutile P25 TiO2) under visible light irradiation. Furthermore, the TiO2 was modified using graphene quantum dots to evaluate their effect on photocatalytic efficiency. The characterization results of the GQDs/TiO2 photocatalyst composites demonstrated that GQDs …
Temperature Control In The Steam Methane Reformer Using Model Predictive Control Based On A Neural Network Model, Rasiq Dipta Alkindi
Temperature Control In The Steam Methane Reformer Using Model Predictive Control Based On A Neural Network Model, Rasiq Dipta Alkindi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hydrogen is a critical energy vector, and magnetic heating reactors represent a promising production technology where current-induced magnetization raises system temperature. Due to the nonlinear and complex thermal dynamics, this study applies a hybrid Echo State Network (ESN) and Long Short-Term Memory (LSTM) model to capture system behavior, combining ESN’s nonlinear dynamic identification with LSTM’s ability to learn long-term dependencies. Hyperparameters were optimized for best performance at 30 reservoir nodes, 0.5 spectral radius, 0.9 connectivity, batch size 4, 50 LSTM units, and 60 epochs. The ESN-LSTM models with 3-input and 4-input feature sets were tested on three winding coil geometries …
Graphene Quantum Dot Spray-Coated Indium Tin Oxide Electrode For Fe3+ Detection, Firadao Bennui
Graphene Quantum Dot Spray-Coated Indium Tin Oxide Electrode For Fe3+ Detection, Firadao Bennui
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ferric ion (Fe3+) contamination in water sources poses significant risks, making reliable detection technologies essential. In this study, electrochemical sensors were developed by spray-coating Graphene quantum dots (GQDs) on indium tin oxide (ITO) electrodes to enhance Fe3+ detection in aqueous systems. The performance of Assembly GQDs and GQDs on ITO electrodes was compared, and the electrochemical sensing of Fe3+ was investigated. GC-358 exhibited a 3D structure with aggregated particles and high electroconductivity, while CLS-3 showed a broad absorption peak around 300 nm and green photoluminescence at 505 nm due to carboxyl groups. Cyclic voltammetry showed the highest current response for …
Lead-Free Perovskite/Metal Oxide Heterojunction Photocatalyst For Sustainable Toluene Oxidation, Zakarya Hazaea
Lead-Free Perovskite/Metal Oxide Heterojunction Photocatalyst For Sustainable Toluene Oxidation, Zakarya Hazaea
Chulalongkorn University Theses and Dissertations (Chula ETD)
An important field of study is the ecologically benign synthesis of useful compounds such as benzaldehyde and benzyl alcohol from the organic contaminant toluene. Lead-free halide perovskites are excellent options for photocatalysis due to their exceptional photoelectric properties. Nonetheless, they have notable challenges, such as fast charge recombination and ineffective charge separation. In this work, we present a simple anti-solvent technique to create a heterojunction between lead-free halide perovskite Cs2AgBiBr6 (CABB) with Cu2O and Cu-Cu2O. This combination facilitates the photocatalytic activation of C(sp3)−H bonds, which in turn increases the oxidation of toluene. The Cu2O and Cu-Cu2O creating a Z-scheme heterojunction …
Effect Of Graphene Nanoplatelets Addition During Electroless Plating Of Abs On The Quantity Of Pdcl2 Usage For Copper-Nickel-Chromium Coated Abs, Wantana Chuakamhod
Effect Of Graphene Nanoplatelets Addition During Electroless Plating Of Abs On The Quantity Of Pdcl2 Usage For Copper-Nickel-Chromium Coated Abs, Wantana Chuakamhod
Chulalongkorn University Theses and Dissertations (Chula ETD)
Acrylonitrile Butadiene Styrene (ABS) with chromium coating is widely used in applications requiring high strength, durability, and aesthetic appeal, such as automotive parts, electronics, appliances, sanitary fixtures, and decorative consumer goods. Before electroplating, nickel electroless plating is applied to ABS to create a conductive base, but this process traditionally relies on palladium (Pd), a costly material. This research explores reducing Pd usage by incorporating graphene into the plating bath, enabling a decrease in Pd concentration from the industrial standard of 16-25 ppm to just 6 ppm with the addition of 15 mg/L of graphene. The Ni-coated ABS achieved an electrical …
Process Simulation And Techno-Economic Evaluation Of Free Lutein Production From Marigold Flowers, Yada Meayrin
Process Simulation And Techno-Economic Evaluation Of Free Lutein Production From Marigold Flowers, Yada Meayrin
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lutein is a carotenoid widely recognized for its health benefits, including improved vision, cognitive function, and prevention of age-related diseases. This study presents a comprehensive techno-economic and environmental assessment of three crude free lutein production processes using marigold flowers (Tagetes erecta L.) at a processing capacity of 74 tons/year, modeled in Asplen Plus V.11. The evaluated processes include sequential extraction and de-esterification (SQP) using hexane (HEX) or liquefied dimethyl ether (LiqDME), and a one-step simultaneous extraction and de-esterification (SMP) using LiqDME. Among these, the SMP-DME process demonstrated the best performance, with a net present value (NPV) of 146.98 million US$, …
Aluminium-Doped And Carbon-Supported Zinc Oxide Ternary Composite Electrodes For Supercapacitor Applications, Abdulkadeem Sanni
Aluminium-Doped And Carbon-Supported Zinc Oxide Ternary Composite Electrodes For Supercapacitor Applications, Abdulkadeem Sanni
Chulalongkorn University Theses and Dissertations (Chula ETD)
Developing high-performance supercapacitor electrodes requires materials with optimized electrical conductivity, surface area, morphology, energy density, and cyclability. Herein, we report a facile hydrothermal synthesis of carbon nanotubes (CNTs)-supported Al-doped ZnO@CuO composite. Structural characterization reveals that Al doping and CuO incorporation can transform ZnO nanoflakes into nanorod/nanoflower heterostructures. The electrochemical analysis of the quaternary composite in a mixed electrolyte containing 2 M KOH, 0.2 M KFC, and 0.2 M KI exhibits a specific capacitance of 1860 F/g at 1 mV/s. The fabricated asymmetric supercapacitor (ASC) yields an energy density of 36 Wh/kg, a power density of 3502.8 W/kg at 30 mA/g, …
Tuning Selectivity Of Ni/Al2o3 Catalysts In Co2 Hydrogenation By Addition Of N, S-Doped Carbon, Nipitpon Jarumalai
Tuning Selectivity Of Ni/Al2o3 Catalysts In Co2 Hydrogenation By Addition Of N, S-Doped Carbon, Nipitpon Jarumalai
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates the enhancement of Ni/Al₂O₃ catalysts for CO₂ hydrogenation by incorporating nitrogen and sulfur co-doped carbon (NSC). A series of catalysts Ni/Al2O3 and its NSC-modified counterparts (Ni1NSC/Al2O3, Ni3NSC/Al2O3, Ni7NSC/Al2O3, and Ni15NSC/Al2O3) were synthesized via thermal treatment under a nitrogen atmosphere and systematically characterized. Techniques including TGA, Raman spectroscopy, and XPS confirmed successful NSC incorporation. Further structural and surface analysis using TEM, XRD, CO-IR, CO2-TPD, H2-TPD, and H2-TPR revealed that NSC modification influenced Ni dispersion, surface basicity, hydrogen activation, and the electronic state of Ni species. Catalytic performance was evaluated in a fixed-bed reactor under a CO2:H2 ratio of …
Arsenic Removal From Synthetic Produced Water Using Ionic Extractants And Vegetable Oils Via Hollow Fiber Supported Liquid Membrane, Natthawan Srinam
Arsenic Removal From Synthetic Produced Water Using Ionic Extractants And Vegetable Oils Via Hollow Fiber Supported Liquid Membrane, Natthawan Srinam
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis presents the separation of arsenic from water derived from synthetic petroleum production using a hollow fiber supported liquid membrane (HFSLM) system. The membrane system incorporates an ionic liquid extractant and a vegetable oil-based diluent. The study began with the selection of suitable extractants and diluents, followed by experimental design to determine optimal operating conditions using response surface methodology (RSM). Box-Behnken Design (BBD) and Central Composite Face-Centered Design (FCCD) were employed, and the data were analyzed through analysis of variance (ANOVA). Kinetic and thermodynamic studies revealed that the HFSLM system could achieve arsenic extraction and stripping efficiencies of up …
Detection And Replacement Of States With Spikes And Noise By Long Short-Term Memory Models Or Neural Networks, Ittikorn Yutto
Detection And Replacement Of States With Spikes And Noise By Long Short-Term Memory Models Or Neural Networks, Ittikorn Yutto
Chulalongkorn University Theses and Dissertations (Chula ETD)
Spike signals are impulsive disturbances with high amplitude occurring over a very short duration. They are typically caused by external factors such as temperature fluctuations, vibrations, or sensor inaccuracies, leading to erroneous measurements and potential degradation of control system performance. This study aims to develop a Long Short-Term Memory (LSTM) model for detecting and replacing spike signals in a second-order system. The model was trained and validated using datasets contaminated with spike signals of varying amplitudes. Experimental results demonstrated that the proposed model could suppress spike amplitudes by up to 99.79%, with a minimum reduction of 92.42% and an average …
Development Of Quaternized Poly(Vinyl Alcohol)/Chitosan/Two-Dimensional Molybdenum Disulfide Anion Exchange Membrane As A Separator For Electrochemical Processes, Nuttapon Suppanucroa
Development Of Quaternized Poly(Vinyl Alcohol)/Chitosan/Two-Dimensional Molybdenum Disulfide Anion Exchange Membrane As A Separator For Electrochemical Processes, Nuttapon Suppanucroa
Chulalongkorn University Theses and Dissertations (Chula ETD)
In response to the global shift toward the expansion of large-scale energy storage systems (ESSs), secondary zinc-air batteries (ZABs) have attracted significant attention as promising candidates for next-generation batteries due to their high energy density, cost-effectiveness, and safety. However, their long-term practical application is hindered by several challenges associated with the membrane separator, including the formation of resistive zinc oxide layers and low hydroxide-ion conductivity. These limitations are attributed to poor ion-selectivity, which impedes electrochemical reactions and degrades battery performance. To address these issues, this study developed a series of innovative membrane separators featuring quaternary ammonium (QA)-functionalized polyvinyl alcohol (PVA), …
Hydrogen Production From Glycerol Using Sorption Enhanced Chemical Looping Steam Reforming With Multifunctional Pellet Catalyst, Talita Nimmas
Hydrogen Production From Glycerol Using Sorption Enhanced Chemical Looping Steam Reforming With Multifunctional Pellet Catalyst, Talita Nimmas
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, the synthesis of a pellet-scale material for hydrogen (H₂) production from glycerol via the Sorption Enhanced Chemical Looping Steam Reforming (SE-CL-SGR) process was investigated. The research focuses on material synthesis, performance enhancement, and the economic and environmental advantages of the developed material. Among the synthesis methods compared, the Stepwise Calcination process demonstrated the best performance, producing structurally stable and mechanically robust pellets. The optimal CaO/support mass ratio for the Ni-supported material (15Ni(70Ca.30Support)) was found to achieve 90% v/v H₂ purity with a pre-breakthrough time of approximately 75 minutes. Rare-earth metal oxides (CeO₂, La₂O₃) addition also improved mechanical …
Regeneration By Electrodialysis Of Secondary Spent Monoethanolamine Solution Obtained After Mineralisation Of Captured Carbon Dioxide With Calcium Sulfate, Ketwarang Nimnualrat
Regeneration By Electrodialysis Of Secondary Spent Monoethanolamine Solution Obtained After Mineralisation Of Captured Carbon Dioxide With Calcium Sulfate, Ketwarang Nimnualrat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The greenhouse effect has been impacting our planet further than we even realized. In recent years, the earth’s atmosphere has rapidly changed at a faster pace than ever. The main villain, mostly released from industry, is carbon dioxide (CO2), which contributes about 79.7 percent of total greenhouse gases. Consequently, Carbon Capture, Utilization and Storage (CCUS) has now become an important role to mitigate this problem. A widely used industrial medium for capturing CO2 is aqueous solution of monoethanolamine (MEA), which is capable of capturing CO2 from fossil fuel-fired processes. However, current MEA regeneration by stripping has high energy requirements for …
Enhance Effectiveness Of Monitoring Scheme Using Insar On Tailings Storage Facility No. 2, Chatree Gold Mine, Thailand, Shanghai Chea
Enhance Effectiveness Of Monitoring Scheme Using Insar On Tailings Storage Facility No. 2, Chatree Gold Mine, Thailand, Shanghai Chea
Chulalongkorn University Theses and Dissertations (Chula ETD)
Tailings storage facility (TSF) is a critical component of the mining industry, serving to safely contain waste generated during mineral extraction. At Chatree Gold Mine, the largest and only active gold mine in Thailand, TSF No.2 handles approximately 5 million tons of tailings annually. Effective monitoring of the facility is crucial for hazard prevention and regulatory compliance. This study aims to enhance the monitoring scheme of TSF No.2 by employing Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique, processed via MintPy software, to analyze ground deformation. Despite traditional monitoring methods, such as in-situ geodetic surveying, offering valuable insights, they …
Recovery Of Tin From Kaolin Mine Tailing, Rangoon, Thailand, Archana Pandit
Recovery Of Tin From Kaolin Mine Tailing, Rangoon, Thailand, Archana Pandit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates the recovery of tin from kaolin waste using gravity, electrostatic, and magnetic separation techniques. A total of 123.500 kg of sand and 103.200 kg of silt were processed using a shaking table, spiral concentrator, high-tension separator, induced roll magnetic separator, and Frantz magnetic separator. Mineralogical and chemical characterization was conducted using X-ray diffractometer (XRD), X-ray fluorescence (XRF), and microscopic analysis to determine tin distribution and occurrence. Experimental results showed that the silt fractions generally exhibited higher tin content than the sand fractions. In this study, Case A refers to the samples (Sand A and Silt A) processed …
Ethanol-Assisted Co2 Hydrogenation To Methanol In A Trickle-Bed Reactor, Pattarapol Akeakkharanusorn
Ethanol-Assisted Co2 Hydrogenation To Methanol In A Trickle-Bed Reactor, Pattarapol Akeakkharanusorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
The hydrogenation of carbon dioxide (CO2) to methanol is a promising approach for CO2 utilization. However, conventional methanol synthesis is thermodynamically limited at high temperatures. Alcohol-assisted methanol synthesis has emerged as a novel low-temperature method, using alcohol as a catalytic solvent to alter reaction pathways. Equilibrium analysis using Gibbs free energy minimization in Aspen Plus showed that increasing ethanol enhanced CO2 conversion and methanol yield. At high ethanol concentrations, ethanol remained in the liquid phase. This study investigated ethanol-assisted CO2 hydrogenation in a trickle-bed reactor using a commercial Cu/ZnO/Al2O3 catalyst. CO2 and H2 were introduced in gaseous form, while ethanol …
Simulation Study For Enhancing Thermal Performance Of Cotton Facemasks Through Integration Of Organic Phase Change Materials, Poptham Chaviengpop
Simulation Study For Enhancing Thermal Performance Of Cotton Facemasks Through Integration Of Organic Phase Change Materials, Poptham Chaviengpop
Chulalongkorn University Theses and Dissertations (Chula ETD)
Climate change has caused temperature extremities around the world. Maintaining body temperature against cold temperatures is important for preventing long term health risks. PCM incorporated facemasks offers the solution to this problem. In this study, computational fluid dynamics utilizing laminar flow of air in a simulated wind chamber is used to model the human breathing cycle in cold environments (0-10°C) through four different types of PCM incorporation facemasks (random, coating, hollow fiber, and lamination) used in the industry and three separate PCM candidates (n-octadecane, capric acid, and PEG-600). The findings indicates that the facemask utilizing the coating PCM incorporation method …
Photocatalytic Activity Of N, S-Cqds/Tio2 Composites For The Degradation Of Methylene Blue Under Light Irradiation, Thanyapak Akkharaamnuay
Photocatalytic Activity Of N, S-Cqds/Tio2 Composites For The Degradation Of Methylene Blue Under Light Irradiation, Thanyapak Akkharaamnuay
Chulalongkorn University Theses and Dissertations (Chula ETD)
Water pollution from synthetic dyes like methylene blue (MB), especially from textile industries, poses serious environmental challenges due to their resistance to conventional treatment. This study focuses on the develops nitrogen and sulfur co-doped carbon quantum dots (N, S-CQDs) incorporated into titanium dioxide (TiO2) for the degradation of methylene blue under light irradiation. The composites were calcined at 400 °C and 500 °C to investigate the effect of calcination temperature on photocatalytic performance. Characterization was conducted using techniques such as XRD, SEM-EDX, TEM, FT-IR, UV–Vis spectroscopy, Photoluminescence, and BET analysis. The results revealed that increasing the calcination temperature enhanced crystallinity, …
Regeneration Of Carbon Dioxide-Rich Amines Via Mineralization, Tanasorn Thumpanisakool
Regeneration Of Carbon Dioxide-Rich Amines Via Mineralization, Tanasorn Thumpanisakool
Chulalongkorn University Theses and Dissertations (Chula ETD)
Carbon dioxide (CO2) a major driver of the increasing greenhouse effect, making the development of CO2 capture and utilization technologies. Although monoethanolamine (MEA) is a highly efficient sorbent, the energy cost of its thermal regeneration remains a significant challenge. This thesis investigates a low-energy regeneration route for MEA based on mineralized CO2. Especially, the study systematically investigates the effects of MEA concentration, calcium source selection, and amine regeneration mechanisms. A 5 M MEA solution achieved a CO2 loading capacity up to 2.9 mol/L. However, mineralization with CaSO4 alone resulted in irreversible MEA protonation and poor reusability. Mechanistic analysis revealed that …
Design And Development Of A Sustainable Ethylene Glycol Production Process Via Electrochemical Co2 Reduction, Nichapat Leelalertwong
Design And Development Of A Sustainable Ethylene Glycol Production Process Via Electrochemical Co2 Reduction, Nichapat Leelalertwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Addressing the critical issue of rising atmospheric CO2 concentrations and their impact on climate change necessitates innovative technological solutions. This study presents a novel and sustainable method for producing ethylene glycol, commonly used in antifreeze, polyester, and various industrial applications, through electrochemical CO2 reduction, offering a lower environmental impact compared to conventional coal-based or biomass-based processes. This process is known as the "OCEAN" technique, which utilizes oxalic acid as a key intermediate to enhance efficiency and minimize unwanted byproducts. The process was simulated in Aspen Plus to evaluate both technological performance and environmental impact. CO2 is converted to oxalic acid …