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Articles 1381 - 1410 of 2554
Full-Text Articles in Engineering
Semi-Supervised Thai Sentence Segmentation Using Local And Distant Word Representations, Chanatip Saetia
Semi-Supervised Thai Sentence Segmentation Using Local And Distant Word Representations, Chanatip Saetia
Chulalongkorn University Theses and Dissertations (Chula ETD)
A sentence is typically treated as the minimal syntactic unit used for extracting valuable information from a longer piece of text. However, in written Thai, there are no explicit sentence markers. We proposed a deep learning model for the task of sentence segmentation that includes three main contributions. First, we integrate n-gram embedding as a local representation to capture word groups near sentence boundaries. Second, to focus on the keywords of dependent clauses, we combine the model with a distant representation obtained from self-attention modules. Finally, due to the scarcity of labeled data, for which annotation is difficult and time-consuming, …
A Model Predictive Control Strategy Based On Predicted Mean Vote For A Building Hvac System, Chanthawit Anuntasethakul
A Model Predictive Control Strategy Based On Predicted Mean Vote For A Building Hvac System, Chanthawit Anuntasethakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis proposes a design of a supervisory model predictive controller for a heating-ventilation-air-conditioning (HVAC) control system. The control objective is to minimize the operating cost and take into account of electrical load shaving and thermal comfort of users. To ensure that thermal comfort is well regulated, we utilize the Predicted Mean Vote (PMV) as an indicator and determine an acceptable bound of a desired set-point temperature. The control design consists of two layers, namely, a supervisory control (SC) layer and a model predictive control (MPC) layer. For the SC layer, we explore a configuration including the choice of predesign …
A Comparative Simulation Of Glycerol Steam Reforming With Foam And Conventional Pellet Catalysts In Packed Bed Reactor, Chattharika Phitchayakorn
A Comparative Simulation Of Glycerol Steam Reforming With Foam And Conventional Pellet Catalysts In Packed Bed Reactor, Chattharika Phitchayakorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to study the effect of different catalyst structures to the hydrogen production process with glycerol steam reforming in packed bed reactors via the COMSOL Multiphysics program. 2D pseudo-homogeneous steady-state model of a 6-inch diameter adiabatic reactor has been developed to describe a transport phenomenon inside the packed bed reactors with two different catalyst structures of conventional 1-inch pellet catalyst and 10-30PPI foam catalyst. The simulated results show that the novel foam catalyst improved the process performance in terms of pressure drop and hydrogen yield comparing to the conventional 1-inch pellet catalyst. The reactor packed with the conventional …
Optimal Sizing Of Battery Energy Storage System With Rooftop Pv Generation System, Chawin Prapanukool
Optimal Sizing Of Battery Energy Storage System With Rooftop Pv Generation System, Chawin Prapanukool
Chulalongkorn University Theses and Dissertations (Chula ETD)
With a significant growth of the rooftop photovoltaic systems (PVs) under the behind-the-meter scheme (BTMS), the battery energy storage systems (BESS) have been developed to enhance the performance of rooftop PVs in many aspects, especially the electricity charge savings. The BTMS can be typically classified into three schemes of self-consumption scheme, net-metering scheme, and net-billing scheme. Other than these schemes, the solar power purchase agreement (SPPA) has been developed to be one the most attractive business models. The SPPA is the scheme where the investors propose to directly sell an electricity from rooftop PVs with BESS to the customers without …
An Assessment Of Root Reinforcement On Soil Slope Using Centrifuge And Numerical Modelling, Gayuh Aji Prasetyaningtiyas
An Assessment Of Root Reinforcement On Soil Slope Using Centrifuge And Numerical Modelling, Gayuh Aji Prasetyaningtiyas
Chulalongkorn University Theses and Dissertations (Chula ETD)
The extreme rainfall as an effect of climate change has been considered as the main problem due to landslide hazard. The rainfall can trigger slope failure through the kinetic energy of raindrop and decreasing of soil resistance due to the increasing of pore water pressure. Vegetation is considerably as low cost and environmentally friendly slope reinforcement. The root specifically provides high contribution in strengthen the soil through the root-soil interaction. However, there is a gap between slope reinforcement by root modelling and field assessment result. The gap is an impact of indirect linked between laboratory modelling and existing vegetated slope …
Implementation Of Traffic Engineering With Segment Routing And Opendaylight Controller On Emulated Virtual Environment Next Generation (Eve-Ng), Htain Lynn Aung
Implementation Of Traffic Engineering With Segment Routing And Opendaylight Controller On Emulated Virtual Environment Next Generation (Eve-Ng), Htain Lynn Aung
Chulalongkorn University Theses and Dissertations (Chula ETD)
Internet service providers and enterprise networks face rapid changes and rapid growth of the internet, and the networks become complex in operations to support the strict Service-level Agreements (SLAs) needed applications. Segment Routing (SR) is a source routing technology that overcomes the conventional Multiprotocol Label Switching (MPLS) networks' drawbacks in scalability, flexibility, and applicability in Software-defined Networking (SDN). SR enables the source device to instruct the path using a segment or list of segments to go through the network. SR can be implemented in IPv6 and MPLS. A segment can be defined as information that instructs SR capable nodes to …
Property Estimation Of Palmitoylethanolamide And Sucrose Palmitate For Process Design From Methyl Palmitate, Janetiya Wongprathed
Property Estimation Of Palmitoylethanolamide And Sucrose Palmitate For Process Design From Methyl Palmitate, Janetiya Wongprathed
Chulalongkorn University Theses and Dissertations (Chula ETD)
Methyl palmitate is the primary component of palm oil-based biodiesel. It is a saturated fatty acid methyl ester which has a high melting point that results in low cold flow properties of biodiesel. Besides, lack of government support may affect the revenue of biodiesel business. For that reason, the producers turn attention to using biodiesel as a raw material for the production of value-added chemicals. Initially, we selected the studied products based on the gross profit margin, production process, market demand and application. This work simulated the production of palmitoylethanolamide, sucrose palmitate and normal alkanes from methyl palmitate using Aspen …
A Study Of Customers' Willingness To Purchase Organic Fresh Milk In Thailand, Jeerawan Punwaree
A Study Of Customers' Willingness To Purchase Organic Fresh Milk In Thailand, Jeerawan Punwaree
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, most consumers often are care about health due to the COVID-19 and personal needs. Dairy products are specific products that are generally consumed by every age group, from children, teenagers, adults, to the elderly. Organic milk could provide an advantageous alternative for health conscious consumers as it must be certified by government agencies prior to market launching. There are many studies supported that organic milk is more beneficial than conventional milk. Theory of Planned Behavior (TPB) was applied to study the factors affected consumers' willingness to purchase organic fresh milk in Thailand. Through the questionnaire method and analysis by …
Deep Sequential Real Estate Recommendation Approach For Solving Item Cold Start Problem, Jirut Polohakul
Deep Sequential Real Estate Recommendation Approach For Solving Item Cold Start Problem, Jirut Polohakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
The item cold-start problem occurs when a recommendation system cannot recommend new items owing to record deficiencies and new listing omissions. When searching for real estate, users can register a concurrent interest in recent and prior projects. Thus, an approach to recommend cold-start and warm-start items simultaneously must be determined. Furthermore, unrequired membership and stop-by behavior cause real estate recommendations to have many cold-start and new users. This characteristic encourages the use of a content-based approach and a session-based recommendation system. Herein, we propose a real estate recommendation approach for solving the item cold-start problem with acceptable warm-start item recommendations …
A Morphable Fpga Soft Processor Using Llvm Infrastructure Targeting Low-Power Application-Specific Embedded Systems, Ehsan Ali
Chulalongkorn University Theses and Dissertations (Chula ETD)
The reconfigurable computing (RC) aims to combine the flexibility of General-Purpose Processor (GPP) with performance of Application Specific Integrated Circuits (ASIC). There are several architectures proposed since RC's inception in 1960s, but all have failed to become mainstream. The main factor preventing RC to become common practice is its requirement for implementers of algorithms (programmers) to be familiar with hardware design. In RC, a hardened processor cooperates with a dynamic reconfigurable Hardware Accelerator (HA) which is implemented on Field-Programmable Gate Array (FPGA). The HA implements crucial software kernel on hardware to increase performance and its design demands digital circuit expertise. …
Production Of Γ-Valerolactone (Gvl) From One-Pot Cascade Transformation Of Furfural Over Pt/Zeolite-Based Catalysts, Jukkapan Saengin
Production Of Γ-Valerolactone (Gvl) From One-Pot Cascade Transformation Of Furfural Over Pt/Zeolite-Based Catalysts, Jukkapan Saengin
Chulalongkorn University Theses and Dissertations (Chula ETD)
γ-valerolactone (GVL) is a green renewable resource, which can be used as fuel additives, organic solvent in food industries, pharmaceutical intermediates. The direct production of GVL from furfural in a one-pot transformation is highly desirable in order to minimize the use of solvents, the number of unit operations, and the production cost. The cascade reaction was carried out in a single reactor, using a secondary alcohol as the hydrogen donor with acid catalysts (so-called Meerwein–Ponndorf–Verley reaction). In this work, the transfer hydrogenation of furfural with 2-propanal as a hydrogen donor was investigated on various zeolites including of HY with Si/Al …
Electrochemical Reduction Of Carbon Dioxide To Formate On Bi And Bisn Electrodes Prepared By Electrodeposition On Copper Foil, Jutamas Wasombut
Electrochemical Reduction Of Carbon Dioxide To Formate On Bi And Bisn Electrodes Prepared By Electrodeposition On Copper Foil, Jutamas Wasombut
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, The Bix/Cu electrocatalysts were prepared by electrodeposition of Bi on Cu foil, and the BixSny/Cu electrocatalysts were prepared by electrodeposition of Bi and Sn on Cu foil in deposition solution bath with different Bi3+ ion concentrations of 0.05, 0.1, and 0.2 M (Bi0.05/Cu, Bi0.1/Cu, Bi0.2/Cu), while the Sn2+ ion concentration was constant at 0.025 M (Bi0.05Sn0.025/Cu, Bi0.1Sn0.025/Cu, Bi0.2Sn0.025/Cu). The electrocatalysts were characterized by SEM-EDX, XRD, and XPS and tested in the electrochemical CO2 reduction reaction. The results demonstrate that the Bi concentrations in the deposition bath affect the structure of Bi into different forms, including bulky structure …
Experiment And Numerical Study Of The Charge Decay On The Surface Of Pmma Insulator, Kamonporn Malathip
Experiment And Numerical Study Of The Charge Decay On The Surface Of Pmma Insulator, Kamonporn Malathip
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis presents the measurement and simulation of surface charge decay on a polymethyl methacrylate (PMMA) circular disc. The objective of the thesis is to calculate the surface charge density in the 2-dimensional (2D) and the 3-dimensional (3D) models for comparison with the estimated results obtained from experiments, and to study the mechanisms of charge which depends on the thickness of the dielectric disc. For the experiments, a rod-plane electrode arrangement was used to generate the positive corona discharge on surface of 1-, 2- and 10-mm thick PMMA disc. The measured surface potential was used to calculate the electric field …
A Real Estate Valuation Model Using Boosted Feature Selection, Kankawee Chanasit
A Real Estate Valuation Model Using Boosted Feature Selection, Kankawee Chanasit
Chulalongkorn University Theses and Dissertations (Chula ETD)
To estimate real estate values, a complex valuation model based on artificial neural network (ANN) has been established as a successful means in modern machine learning research, specifically when high-dimensional data are available. Unfortunately, the real estate data in many locations, such as Thailand, are quite limited in terms of features. Hence, it becomes mandatory to reduce the complexity using feature selection techniques. These techniques aim to improve performance by identifying significant factors and help decrease the computational overload and model construction. However, due to the lack of explicability and interpretability in ANNs, the analysis of input factors cannot be …
Selective Hydrogenation Of Acetophenone To 1-Phenylethanol On Pt/ Tio2 Catalysts Prepared By Pulsed Dc Magnetron Sputtering, Khunarnon Ditsataporncharoen
Selective Hydrogenation Of Acetophenone To 1-Phenylethanol On Pt/ Tio2 Catalysts Prepared By Pulsed Dc Magnetron Sputtering, Khunarnon Ditsataporncharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
1-Phenylethanol (PHE) is a high-value chemical with various applications in fragrance and pharmaceutical industries. It is extensively used as strawberry fragrance additives in yogurts and chewing gums and an intermediate of anti-inflammatory drugs such as Ibuprofen. In this study, selective hydrogenation of acetophenone (AP) to PHE was investigated using platinum catalysts supported on different types of titanium dioxide including PC500 (pure anatase) and P25 (anatase mixed rutile). Pt was deposited on the titanium dioxide supports by pulsed direct current magnetron sputtering (PDC-MSD) method with deposition time spent on Pt coating at 3, 6, and 9 minutes. For comparison purposes, Pt/TiO2 …
Explainable Stock Price Prediction Using Technical Indicators With Short Thai Textual Information, Kittisak Prachyachuwong
Explainable Stock Price Prediction Using Technical Indicators With Short Thai Textual Information, Kittisak Prachyachuwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
A stock trend prediction has been in the spotlight from the past to the present. Fortunately, there is an enormous amount of information available nowadays. There were prior attempts that have tried to forecast the trend using textual information; however, it can be further improved since they relied on fixed word embedding, and it depends on the sentiment of the whole market. In this paper, we propose a deep learning model to predict the Thailand Futures Exchange (TFEX) with the ability to analyze both numerical and textual information. We have used Thai economic news headlines from various online sources. To …
Redesigning Weakly Supervised Localization Architectures For Medical Images, Konpat Preechakul
Redesigning Weakly Supervised Localization Architectures For Medical Images, Konpat Preechakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Point localization is a task that aims to identify the location but not the extent of an object of interest in an input image. A success localization is when a model predicts a point which is within the boundary of an object of interest. This task has been successfully learnt using only image-level annotation i.e. image classification. This setting is known as weakly-supervised point localization. Weakly-supervised point localization is particularly useful in medical imaging task where not only the decision of a model is required by also the explanation. The better the explanation the more useful the model is. Usually …
Electrochemical Reduction Of Co2 To Co On Zn Electrodes Prepared By Electrodeposition Method, Krongkwan Poonbun
Electrochemical Reduction Of Co2 To Co On Zn Electrodes Prepared By Electrodeposition Method, Krongkwan Poonbun
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, the effect of substrates including Cu and Ti on the catalytic activity of Zn electrocatalysts prepared by electrodeposition method was investigated in the electrochemical reduction of CO2 (CO2ER). As analyzed by SEM-EDX and XRD results, it indicated that the different substrates did not have any influence on the morphologies of catalysts and the conductivity of substrate was the main factor on the CO2ER performance. The effect of Zn precursor concentration in the range of 0.025 M to 0.4 M was further studied on the characteristics and the activity of Zn/Cu catalysts in the CO2ER. . At low …
Determining The Effectiveness Of The Health-Edrm Framework And Twitter Data Analysis As The Near Real-Time Source Of Information During The Covid-19 Situation, Kumpol Saengtabtim
Determining The Effectiveness Of The Health-Edrm Framework And Twitter Data Analysis As The Near Real-Time Source Of Information During The Covid-19 Situation, Kumpol Saengtabtim
Chulalongkorn University Theses and Dissertations (Chula ETD)
Coronavirus pandemic or COVID-19 pandemic is considered to be one of the most severe disasters that affect both lives and economics to all the countries around the world. Health Emergency and Disaster Risk Management Framework or HEALTH-EDRM framework is the disaster management framework established in late 2019. One objective of this framework is to reduce the impact of the disaster that affects the lives of the people. Risk communication which is considered as the main function of this framework is also the main key for reducing the amount of affecting people. In this research, the analysis of the effectiveness of …
A Comparative Study Of Road Traffic Violation Between Thai And Japanese Students, Napattharakorn Katanararoj
A Comparative Study Of Road Traffic Violation Between Thai And Japanese Students, Napattharakorn Katanararoj
Chulalongkorn University Theses and Dissertations (Chula ETD)
During the last ten years. Accidents of vulnerable road users in Thailand have increased significantly and hit the most severe accident in 2017, especially teenagers between 15-19 year-old. When comparing to Japan in 2017, Japan has reached the lowest accident of all-time since 1960. Considering differences, there are differences in attitudes and behavior toward violation behavior. This study aims to analyze the factor affecting violation behavior between Thai and Japanese to determine the appropriate policies and recommendations. By studying road user's behavior and attitude based on the theory of planned behavior (TPB) in Bangkok, Thailand and Sapporo, Hokkaido, Japan. Questionnaires …
Manufacturing Cost Reduction In A Filling Process Of Aerosol Products, Nattagun Charoenbunsupkarn
Manufacturing Cost Reduction In A Filling Process Of Aerosol Products, Nattagun Charoenbunsupkarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focuses on the development of heuristics that help reduce the production cost of an aerosol filling process of a case study company, while satisfying all related constraints, including production capacity and due dates. The proposed heuristics are a two-phase one, where the initial solutions are first constructed based on simple dispatching rules, and, once completed, such solution is then iteratively improved by two different improvement heuristics, namely 2OPT and Node Shift. A tabu list is also embedded within such a framework to help reduce its computational time. We have assessed the performances of these heuristics based on 6 …
Comparative Study Of Gross Split And Cost Recovery Production Sharing Contracts In Indonesia, Mohammad Ubaidillah
Comparative Study Of Gross Split And Cost Recovery Production Sharing Contracts In Indonesia, Mohammad Ubaidillah
Chulalongkorn University Theses and Dissertations (Chula ETD)
In upstream oil and gas business, Indonesian has introduced Production Sharing Contract Cost Recovery (PSC CR) in 1966 and still implementing that fiscal system until nowadays. In January 2017, The Indonesian Minister of Energy and Mineral Resources (MEMR or ESDM) introduce new PSC system called Production Sharing Contract Gross Split (PSC GS) following with three amendments until 2019. Ministries believe this new Fiscal regime can attract more investor to invest Oil & Gas business in Indonesia by delivering three main values which are certainty, efficiency, and simplicity policies. This study evaluates and compares the financial aspect of new Indonesian fiscal …
Detection Of Wagyu Beef Sources With Image Classification Using Convolutional Neural Network, Nattakorn Kointarangkul
Detection Of Wagyu Beef Sources With Image Classification Using Convolutional Neural Network, Nattakorn Kointarangkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Wagyu beef originated in Japan. However, there are many types of Wagyu beef in the market around the globe. Primary sources include Australia, USA, Canada and the United Kingdom. The authentic Japanese Wagyu is well known for its intense marbling, juicy rich flavor and tenderness. Observing that there are differences in flavor, texture, and quality between distinct sources of Wagyu. This research presents an AI-based approach to identify Wagyu beef sources with image classification. The input images were collected from reliable sources on the internet and augmented with DCGAN. Deep neural networks, CNN, was constructed to detect the marbled fat …
Learning Personally Identifiable Information Transmission In Android Applications By Using Data From Fast Static Code Analysis, Nattanon Wongwiwatchai
Learning Personally Identifiable Information Transmission In Android Applications By Using Data From Fast Static Code Analysis, Nattanon Wongwiwatchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
The ease of use of mobile devices has resulted in a significant increase in the everyday use of mobile applications as well as the amount of personal information stored on devices. Users are becoming more aware of applications' access to their personal information, as well as the risk that these applications may unwittingly transmit Personally Identifiable Information (PII) to third-party servers. There is no simple way to determine whether or not an application transmits PII. If this information could be made available to users before installing new applications, they could weigh the pros and cons of having the risk of …
Effect Of Single Metal Loading On Cao/Al2o3 Pellet Catalyst For Biodiesel Production, Nattawadee Munbupphachart
Effect Of Single Metal Loading On Cao/Al2o3 Pellet Catalyst For Biodiesel Production, Nattawadee Munbupphachart
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biodiesel is a sustainable biofuel mainly derived from transesterification of vegetable oil or animal fat. Transesterification is increasingly being catalyzed by heterogeneous catalysts in recent years. As a result of a high-pressure drop, solid base catalysts in a powder form are not suitable for a continuous process. A pellet catalyst is more convenient, but it has lower surface per volume as well as lower in its catalytic activity for transesterification. This research aims at studying the effect of metal oxides loading on CaO/Al2O3 pellet catalyst for improvement of catalytic activity of transesterification. The 20 wt.% single metal loading of metal …
Preparation And Characterization Of Nanopaper From Regenerated Cellulose, Nattorn Paijit
Preparation And Characterization Of Nanopaper From Regenerated Cellulose, Nattorn Paijit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cellulose nanopapers (RCNP) were prepared from regenerated cellulose (RC) via the solvent casting method. RC was prepared by dissolution of bleached eucalyptus cellulose pulp (BEP) with 85% H3PO4 at -20oC. Water was applied as anti-solvent in the regenerated process. Effects of storage time after dissolution on fiber solubility were investigated at 0, 20, 40, 60 min, 1, and 2 days. ATR FT-IR spectra and crystalline index proved that regenerated cellulose was obtained. The crystalline index of the fiber became stable at 60 min, indicating the fibers were completely dissolved at 60 min. The results from thermogravimetric analysis showed that after …
Bias Correction Of Satellite Precipitation Estimates Over Thailand, Nelson Stephen Lising Ventura
Bias Correction Of Satellite Precipitation Estimates Over Thailand, Nelson Stephen Lising Ventura
Chulalongkorn University Theses and Dissertations (Chula ETD)
Over the years, meteorological satellite instruments have produced Satellite Precipitation Estimates (SPEs) that can supply rainfall intensity rates globally. However, these datasets do not directly reflect the actual values of ground measurements so it is imperative to correct the systematic biases of SPEs to produce reliable hydrologic models. Thus, the aim of this study is to assess the effectiveness of bias correction of SPE products over Thailand. The Precipitation Estimates from Remotely Sensed Information using Artificial Neural Networks – Cloud Classification System (PERSIANN-CCS), Global Satellite Mapping of Precipitation - Near Real Time (GSMaP_NRT), and Integrated Multi-satellitE Retrievals for GPM (IMERG) …
Analysis Of Efficiency Of Container Operations With Automated System:A Case Study Of Laemchabang Port, Nichkan Peemdechachai
Analysis Of Efficiency Of Container Operations With Automated System:A Case Study Of Laemchabang Port, Nichkan Peemdechachai
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study analyzed an automated system of container operations at Laem Chabang Port, Thailand. Due to the rapid growth in demand at the port, the throughput volume cannot reach the requirement, has difficulty in unskilled worker recruitment, working hours are limited, and has limitation on the terminal area. Therefore, an automated system is planned to replace the conventional container operations; this will also support the Port Authority of Thailand's encouragement of using automation technology. Along with the increasing the level of port development and enhancement of the container terminal port to be competitive in the world trade arena by developing …
Sodium Doping Effects On Properties Of Czts Thin Filmsfabricated By Sol-Gel Convective Deposition Technique, Orawan Sukchoy
Sodium Doping Effects On Properties Of Czts Thin Filmsfabricated By Sol-Gel Convective Deposition Technique, Orawan Sukchoy
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cu2ZnSnS4 (CZTS) is an interesting candidate for thin-film solar cell applications due to its availability and attractive properties (energy band gap of 1.5 eV and high absorption coefficient). However, CZTS solar cell performance is limited because of the defect formation from small grain size, pinholes, rough surface, and negative defects in CZTS such as CuZn. One of the most possible ways to reduce these negative defects, and to increase solar cell performance is by doping with sodium. In this work, CZTS films were synthesized by sol-gel convective deposition technique and Na was doped in CZTS film using 2 different methods: …
Methanol Synthesis Via Hydrogenation Of Mixed Co/Co2 Over Mn Modified Cu/Zno/Al2o3 Catalyst, Papawin Tunyasitikun
Methanol Synthesis Via Hydrogenation Of Mixed Co/Co2 Over Mn Modified Cu/Zno/Al2o3 Catalyst, Papawin Tunyasitikun
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purposes of this study are to investigate the methanol synthesis by using mixed CO/CO2 hydrogenation on Mn modified Cu/ZnO/Al2O3 catalyst which is prepared by the co-precipitation method and to investigate the overall energy consumption of methanol synthesis based on experimental results through the simulation process using Aspen Plus V.9. The improvement of catalytic activity is performed by a continuous fixed bed microreactor at 250°C under atmospheric pressure for 5 hours on the stream through hydrogenation of different feed composition of CO2/H2, CO/H2, and CO/CO2/H2, and 24000 ml/gcat∙h of GHSV. The physical and chemical properties of the catalysts are measured …