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The Effect Of Disking Technique On Proximal Caries Of Primary Upper Incisors In Tribal Preschool Children Attending Child Development Centers Of Mae Fah Luang District, And Doi Tung Development Project, Chiang Rai, Niwat Thanaboonyang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Aim: To evaluate the effect of disking technique and resin modified glass ionomer cement (RMGI) restoration on proximal caries of primary upper incisors in tribal preschool children, aged 3-5 years, attending child development centers of Doi Tung Development Project, Chiang Rai. Methods: Twenty tribal preschool children were enrolled in this match-paired design study. Twenty-six proximal carious surfaces were randomized for RMGI restoration (control group), and 26 proximal carious surfaces were randomized for disking technique (experimental group). Fluoride varnish was applied in both groups after treatment. At 6-month interval, the treatment success was evaluated including retention of restoration, marginal integrity, no …
Association Between Chronic Periodontitis And Hypertension Among Thai Adults, Ploysiri Rassamee
Association Between Chronic Periodontitis And Hypertension Among Thai Adults, Ploysiri Rassamee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Previous studies suggest that periodontitis may be associated with an increasing risk of hypertension. However, data from large epidemiological studies are limited. The aim of this cross-sectional study was to examine the association between periodontitis and hypertension using data from a cohort study in a Thai population. The study population comprised of 1,378 employees of the Electricity Generating Authority of Thailand (EGAT), aged 53 to 73 years old, were categorized into no/mild, moderate, or severe periodontitis groups. Hypertension was determined as having systolic blood pressure 140 mmHg or more or diastolic blood pressure 90 mmHg or more, or taking antihypertensive …
Green Composites Of Polylactic Acid Filled With Natural Fiber For Biodegradation Application, Chamaiporn Yamoum
Green Composites Of Polylactic Acid Filled With Natural Fiber For Biodegradation Application, Chamaiporn Yamoum
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focuses on how to use natural fibers available from agricultural residues to produce biodegradable materials such as mulch films. Green composites were prepared from natural fibers (peanut shell and bagasse fiber) and polylactic acid (PLA) together with plasticizers. The presence of plasticizers improved PLA molecular mobility as seen by the reduction of glass transition, cold crystallization, and melting temperatures. The addition of natural fibers into PLA brought down decomposition temperature when compared to PLA. The morphological study of the composites showed poor interfacial adhesion between natural fibers and PLA matrix. Moreover, the loading of plasticizers improved distribution of …
Production Of Biojet Fuel From Palm Fatty Acid Distillate Over Ni/Hzsm-12 Catalyst, Chayanee Hiranyasiri
Production Of Biojet Fuel From Palm Fatty Acid Distillate Over Ni/Hzsm-12 Catalyst, Chayanee Hiranyasiri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Generally, jet fuels are mainly derived from the refining of petroleum feedstock which exhaust greenhouse gases. Therefore, biojet fuel is introduced as an alternative way to solve the problem. Moreover, jet fuel must have a freezing point about -47 °C or below so iso-paraffins which have low freezing point are required. In this study, the hydroprocessing of palm fatty acid distillate (PFAD) over synthesized Ni/HZSM-12 and conventional Ni/HY catalysts which have different morphology and pore size for producing biojet fuel (hydrocarbon in a range of C9-C14) was studied in a continuous flow fixed-bed reactor under conditions of 350-400 °C, 10-30 …
Chance Constrained Optimization For Petrochemical Supply Chain With The Validation Technique, Kan Rungphanich
Chance Constrained Optimization For Petrochemical Supply Chain With The Validation Technique, Kan Rungphanich
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, the profit is more concern in industry due to high business competition. Therefore, reducing the cost is needed to survive competition. Stochastic optimization had been interesting method to reduce opportunity and over-demand loss in the supply chain under uncertainties. Chance constrained optimization is one of the approaches to stochastic optimization. The uncertainties are included in chance constraint of event under level of confidence. This method is used to design the realistic supply chain giving more stabilities than deterministic optimization. The two case studies have been used to show the effectiveness of chance constrained optimization: the simple supply chain network …
Methane And Carbon Dioxide Adsorption On Al-Based And Zr-Based Mofs: Effects Of Amino-Functionalization, Orawee Lamoonkit
Methane And Carbon Dioxide Adsorption On Al-Based And Zr-Based Mofs: Effects Of Amino-Functionalization, Orawee Lamoonkit
Chulalongkorn University Theses and Dissertations (Chula ETD)
For natural gas storage, adsorbed natural gas (ANG) technology has attracted great attention. There is a wide range of porous materials for ANG, but the most promising porous adsorbents for natural gas are metal organic frameworks (MOFs). This study examined adsorption of carbon dioxide and methane gases on aluminium (Al) based MOFs and zirconium (Zr) based MOFs including MIL-53(Al), MIL-53(Al)-NH₂, UiO-66, UiO-66-NH₂ 25%, UiO-66-NH₂ 50%, UiO-66-NH₂ 75%, and UiO-66-NH₂. Experiments were carried out in a static system at 33°C and pressures up to 100 psi. Characterization and structural analysis of the adsorbents were investigated by Fourier transform infrared spectroscopy (FTIR), …
Novel Microemulsion Formation By The Hydrophilic- Lipophilic Deviation Concept Using Carboxylate Extended Surfactants For Eor Application, Suchawadee Kumkhuntod
Novel Microemulsion Formation By The Hydrophilic- Lipophilic Deviation Concept Using Carboxylate Extended Surfactants For Eor Application, Suchawadee Kumkhuntod
Chulalongkorn University Theses and Dissertations (Chula ETD)
The Winsor type III (middle phase) microemulsion formation is widely used for enhanced oil recovery (EOR) application. A novel carboxylate surfactant has been an attractive surfactant for the oil recovery due to high chemical stability in harsh reservoir conditions (i.e., high brine concentration and high temperature). This study aims to formulate the middle phase microemulsion in order to obtain the minimum IFT and high solubilization capacity with binary anionic surfactant system using sodium dioctyl sulfosuccinate (AOT) and carboxylate extended surfactants with varying the polyethylene oxide number (EO = 2, 4 and 6) at three mixing molar ratios of 5:5, 7:3 …
Detergency Of Mixed Oily And Particulate Soils By Single And Mixed Surfactant Systems, Thanawan Teerasathittham
Detergency Of Mixed Oily And Particulate Soils By Single And Mixed Surfactant Systems, Thanawan Teerasathittham
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research studies the detergency performance of mixed surfactants of (anionic and nonionic surfactants) for mixed oily and particulate soils on polyester/cotton blend fabric, and compares with a commercial liquid detergent. Palm oil and kaolinite are used as representatives of oily soil and particulate soil, respectively. The anionic surfactants used in this study are methyl ester sulfonate (MES), linear alkyl benzene sulfonate (LAS) and sodium dodecyl sulfate (SDS). The nonionic surfactants are alcohol ethoxylate 7EO (AE7) and alcohol ethoxylate 9EO (AE9). The effect of surfactant concentrations, NaCl concentration, and mixing ratios of the selected surfactant formulations on detergency performance are …
Evaluation Of Environmental Impacts For Non-Metallic Part In Waste Printed Circuit Boards (Pcbs) Using Combined Material Flow Analysis (Mfa) And Life Cycle Assessment (Lca), Warisara Rungsitikul
Evaluation Of Environmental Impacts For Non-Metallic Part In Waste Printed Circuit Boards (Pcbs) Using Combined Material Flow Analysis (Mfa) And Life Cycle Assessment (Lca), Warisara Rungsitikul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Printed circuit boards (PCBs) have become common components in most electric and electronic equipment. Because of their wide ranges of application, waste PCBs is becoming one of the most rapidly growing wastes. Recycling of waste PCBs is an important subject not only for the protection of the environment but also for the recovery of valuable metals. This study aimed to evaluate the waste PCBs management strategies using the combination of material flow analysis (MFA, STAN v.2.6.801) and life cycle assessment (LCA, SimaPro v.8.3.0.0) methods. The waste management scenario was considered for three different options; disposal of the waste PCBs (Option …
Removal Of Mixed Vocs Of Benzene, Toluene, And Xylene By Using Catalytic Corona Discharge System, Issaree Tantiprapa
Removal Of Mixed Vocs Of Benzene, Toluene, And Xylene By Using Catalytic Corona Discharge System, Issaree Tantiprapa
Chulalongkorn University Theses and Dissertations (Chula ETD)
Silver (Ag) and Manganese (Mn) catalysts were loaded on TiO₂ and Al₂O₃ supports on quartz wool that were tested for the oxidation of mixed Volatile Organic Compounds (VOCs) of benzene, toluene, and xylene in nonthermal plasma corona discharge. The total feed concentration of VOCs was fixed at 100 ppm. The catalyst located between the pin and plate electrodes with a constant gap distance of 15 mm and the pin and plate plasma reactor had an inside diameter of 9 mm. The outlet stream was analyzed by gas chromatography equipped with TCD and FID detectors. The operating parameters including applied voltage, …
Polyisocyanurate Foams Preparation Catalyzed By Mixtures Of Copper-Amine Complexes/Potassium 2-Ethylhexanoate, Teeraporn Suwannawet
Polyisocyanurate Foams Preparation Catalyzed By Mixtures Of Copper-Amine Complexes/Potassium 2-Ethylhexanoate, Teeraporn Suwannawet
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, a new catalyst system for the preparation of polyisocyanurate (PIR) foam was developed. The mixture of copper-amine complex:potassium 2-ethylhexanoate (K-15) and metal-ethanolamine complex:K-15 were used as catalysts. Two copper-amine complexes and two metal-ethanolamine complexes, namely Cu(OAc)2(en)2, Cu(OAc)2(trien), Cu(OAc)2(EA)2 and Zn(OAc)2(EA)2, respectively; where en = ethylene diamine, trien = triethylenetetramine and EA = ethanolamine, were used as catalyst for blowing and gelling reactions. K-15 was used as a catalyst for trimerization reaction. These catalysts could be further used in the preparation of PIR forms without purification. Characterization of catalysts were done by using UV-visible spectroscopy. The factors investigated …
Improved Barrier Properties Of Pp/Ldpe Composite Film: Effect Of Montmorillonite And Poly (Lactic Acid), Supornpat Mooninta
Improved Barrier Properties Of Pp/Ldpe Composite Film: Effect Of Montmorillonite And Poly (Lactic Acid), Supornpat Mooninta
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the properties of polypropylene (PP) were improved for single layer film application by incorporating low density polyethylene (LDPE), poly(lactic acid) (PLA) and montmorillonite (MMT). The polymer composites was prepared by melt blending using a twin screw extruder and the film was produced by cast film extruder. The addition of LDPE in PP improved the elongation at break and tear strength. The PP/LDPE blend at the ratio of 80:20 (w/w) was selected for blending with PLA and MMT and the PP/LDPE/PLA/MMT composite showed the increased tensile modulus while the elongation at break decreased with increasing PLA and MMT …
Surface-Enhanced Raman Scattering Technique For Polycyclic Aromatic Hydrocarbons Detection Using Thiol-Functionalized Silver Nanoparticle Films, Sathita Taksadej
Surface-Enhanced Raman Scattering Technique For Polycyclic Aromatic Hydrocarbons Detection Using Thiol-Functionalized Silver Nanoparticle Films, Sathita Taksadej
Chulalongkorn University Theses and Dissertations (Chula ETD)
The detection of polycyclic aromatic hydrocarbons (PAHs) is developed based on surface-enhanced Raman scattering (SERS) using silver nanoparticle films as SERS substrates. The films are fabricated by a Langmuir Blodgett (LB) method and the surface of AgNP films are functionalized with various types of aromatic and aliphatic thiols, i.e., naphthalenethiol, phenylethanethiol, pentanethiol, octanethiol, and dodecanethiol, to create a hydrophobic layer for PAHs to attach on and stay in hot spot. The results indicate that nine kinds of PAHs with different structures, i.e., anthracene, chrysene, naphthacene, naphthalene, phenanthrene, pentacene, perylene, pyrene, and triphenylene, can attach on the surfaces of thiol-modified AgNP …
Preparation And Characterization Of Starch Films Reinforced With Citrate Cellulose Nanocrystals, Prapaporn Nakarat
Preparation And Characterization Of Starch Films Reinforced With Citrate Cellulose Nanocrystals, Prapaporn Nakarat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Citrate-modified bacterial cellulose nanocrystals (citrate CNCs) were prepared by a green one-pot dual acid (citric and hydrochloric acids) method and used them to reinforce three types of starch films; corn, wheat and rice starch films. The average length and width of citrate CNCs were 583 and 46 nm, respectively. The degree of citrate substitution on CNCs was 0.075 and its crystallinity index was closely to the original bacterial cellulose. The effect of various amount of citrate CNCs (0-20%wt of starch) on film property was study. Three starch films showed the same trend of examination results. The film thickness of most …
Adsorption Of Methane And Carbon Dioxide On Activated Carbon And Metal Organic Frameworks, Chutima Sudsuansi
Adsorption Of Methane And Carbon Dioxide On Activated Carbon And Metal Organic Frameworks, Chutima Sudsuansi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Natural gas has gain popularity for transportation among other fuels since it is the cleanest burning fossil fuel. However, the important challenge for utilizing natural gas is its comparatively low volumetric energy storage density. Consequently, a suitable natural gas storage is needed. Adsorbed natural gas (ANG) is an interesting alternative because it could be expected to reduce the cost and potential damage from compressed natural gas (CNG) and liquefied natural gas (LNG) technology. Comparative adsorption of methane and carbon dioxide on activated carbon ZIF-8, UiO-66, and MIL-53 (Al) was investigated at 35 °C and up to 100 psi. The addition …
Identification Of Crude Oils And Fuel Oils After Weathering Using Biomarkers, Pyrogenic Index And Asphaltenes Contents, Hathairat Thongkorn
Identification Of Crude Oils And Fuel Oils After Weathering Using Biomarkers, Pyrogenic Index And Asphaltenes Contents, Hathairat Thongkorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Oil spills have become a global problem. This is one of the serious problems in marine environment. The spills are generally from reservoir zipping, accident or unauthorized drainage. Typically, the spilled oils are fuel oils or crude oils which are difficult to differentiate. After oil spill incident, oils are undergone weathering processes such as evaporation, dissolution, and biodegradation etc., which are main factor of depleting hydrocarbon. This work focuses on the distribution of hydrocarbon and diagnostic ratio of polycyclic aromatic hydrocarbons such as pristane, phytane, phenanthrene, pyrene, chrysene and biomarker in hopane group after weathering processes. Moreover, measuring of Al, …
Preparation Of Alginate Capsule Using Two Coaxial Glass-Tube, Panida Watchanung
Preparation Of Alginate Capsule Using Two Coaxial Glass-Tube, Panida Watchanung
Chulalongkorn University Theses and Dissertations (Chula ETD)
TEMPO-Oxidized bacterial cellulose (TOBC) were obtained using TEMPO-mediated oxidation (TOBC) to produce carboxylate groups on bacterial cellulose surfaces. TOBC had lower crystallinity but better aqueous dispersion than bacterial cellulose. TOBC was used as a reinforcement agent for production alginate capsules. The alginate capsules for entrapping rice bran oil were made via a coaxial-glass tube. The factors that influenced on the shape and production efficiency of capsules were the gap between tube tip and the Ca2+ ions bath and the viscosity of shell solution. However, these factors had no effect on the size and shell thickness of capsules. Increasing of TOBC …
Sustained Release Of Antibiotics From Bone Spacer, Miranda Oungeun
Sustained Release Of Antibiotics From Bone Spacer, Miranda Oungeun
Chulalongkorn University Theses and Dissertations (Chula ETD)
Bone spacer is a device developed to temporarily insert into the body to treat infected tissue caused by bone replacement. Burst release and short-time release of antibiotics from bone spacer not only limits their ability to clear infection but also causes tissue inflammation. Therefore, here we have fabricated bone spacers containing antibiotic-loaded particles, studied their antibiotic release character, and measured the compressive strength of PMMA cements. Four biocompatible particles were investigated. Vancomycin and erythromycin were used as hydrophilic and hydrophobic model drugs, respectively. Rice granules and calcium citrate particles were loaded with vancomycin and gave the percent loading of 84.9 …
Heat Exchanger Network Retrofit Under Fouling Effect, Jaturaporn Yanyongsak
Heat Exchanger Network Retrofit Under Fouling Effect, Jaturaporn Yanyongsak
Chulalongkorn University Theses and Dissertations (Chula ETD)
The energy conservation by heat exchanger network (HEN) is important in process design according to an increase of energy costs and global environmental concerns. To minimize the energy consumption with positive net present value (NPV), the retrofitted HEN plays an important role in process energy systems. The HEN retrofit model is based on stage-wise superstructure by Yee and Grossmann (1990). In addition, fouling deposition on the surface area of heat exchangers causes extra energy consumption, production loss and maintenance costs. The new proposed model is retrofitting HEN with fouling effects. This method achieves HEN with the optimal trade-offs between energy …
Methane Hydrate Formation And Dissociation : Roles Of Promoters, Kimhak Neak
Methane Hydrate Formation And Dissociation : Roles Of Promoters, Kimhak Neak
Chulalongkorn University Theses and Dissertations (Chula ETD)
Roles of promoters become necessary in methane hydrate formation for the attempt of gas storage application, but some additives might cause unwanted results in gas recovery. The effects of amino acids (l-leucine and l-valine) and surfactants, sodium dodecyl sulfate (SDS), and methyl ester sulfonate (MES) was investigated at 8 MPa and 2 to 4 °C. L-leucine system enhanced hydrate formation because of its surface activity and surface adsorption at interfaces. A noticeable methane uptake yield was also observed in the l-valine solution. Its influences might be from the nature of l-valine that has non-polar, aliphatic hydrophobic side chain resulting in …
Optimization Of Single Refrigerant Conocophillips Lng Cascade Process, Naken Saetang
Optimization Of Single Refrigerant Conocophillips Lng Cascade Process, Naken Saetang
Chulalongkorn University Theses and Dissertations (Chula ETD)
An LNG cascade process operates under high pressure and extremely low temperature to liquefy natural gas, requiring very high work input to the compressors. This thesis performed the optimization of the single refrigerant ConocoPhillips LNG process by a global optimization technique based on the domain and image partitioning methodology (Faria and Bagajewicz, 2012) to minimize work input to the system. The procedure consists of an NLP upper bound and MILP lower bound models. The lower bound model was formulated by discretizing and linear relaxation of the upper bound non-linear equations by assigning new integer variables and a set of linear …
Energy And Exergy Analysis For Cryogenic Process Design/Retrofit, Nattawat Threerachannarong
Energy And Exergy Analysis For Cryogenic Process Design/Retrofit, Nattawat Threerachannarong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Energy and Exergy analysis are one of alternative techniques to analyze chemical processes in term of energy quality parameters such as enthalpy, entropy and exergetic temperature. The exergetic temperature can conduct Exergy Composite Curves diagram (ECCs) (Marmolejo-Correa, 2012) which represents exergy targets: exergy requirement, exergy rejection and exergy destruction etc. In addition, these targets can be used for improving processes. The strength points of these analysis are to design the new process and to improve the utility performance. Therefore, these analysis methods have been applied to low-temperature process that requires a large amount of energy consumption. In this work, there …
Removal Of Mixed Vocs Of Benzene, Toluene And Xylene By A Multistage Corona Discharge System, Nitikorn Ditthawat
Removal Of Mixed Vocs Of Benzene, Toluene And Xylene By A Multistage Corona Discharge System, Nitikorn Ditthawat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The oxidation of mixed volatile organic compounds (VOCs) of benzene, tol-uene and xylene in non-thermal plasma corona discharge was investigated. An initial total VOCs concentration of 100 ppm and feed flow rate of 50.0 ml/min were firstly fixed to investigate the effects of an applied voltage and input frequency on VOCs conversion, power consumption and CO₂ and CO selectivities. For a single stage plasma system, under the optimum applied voltage of 8 kV and input frequency of 500 Hz, the system gave the high CO₂ selectivity with the low CO selectivity and the lowest power consumption. At the optimum operationable …
Life Cycle Assessment Of End Of Life Strategies For Waste From Petroleum Production, Nuntawat Urairat
Life Cycle Assessment Of End Of Life Strategies For Waste From Petroleum Production, Nuntawat Urairat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The waste treatment and disposal of oil refining industry sector are one of the significant aspects of environmental concerns. Because they are not only generated in substantial amounts, but also contained with various hazardous substances such as waste oils, spent catalysts, and mercury-contaminated materials. This study aimed to develop and evaluate the waste management strategies, from waste generator (WG) to waste processors (WP), using the material flow analysis (MFA, STAN v.2.6.601) and life cycle assessment (LCA, SimaPro v.8.3.0.0) as an assessment tool. The functional unit is the amount of waste generated from six refineries in the year 2015. The waste …
Kinetics Study For Fischer-Tropsch Synthesis Over Cobalt Catalyst By Kinetic Monte-Carlo Simulation, Nuttawut Pugingna
Kinetics Study For Fischer-Tropsch Synthesis Over Cobalt Catalyst By Kinetic Monte-Carlo Simulation, Nuttawut Pugingna
Chulalongkorn University Theses and Dissertations (Chula ETD)
Kinetic Monte-Carlo simulation was utilized to study the kinetic behaviors of C₁ and C₂ formation in the Fischer-Tropsch synthesis over the cobalt surface by varying reaction conditions. Two reaction models: the carbide mechanism and the CO insertion mechanism were applied to this simulation. The production rates and fractional coverages of each adsorbed species could be calculated under the steady state. Moreover, the combination between carbide and CO insertion mechanism was also studied to suggest the possibility of each reaction mechanism, and compared the results with the reported experimental results under the same conditions. It was ob-served that the C–C bond …
Effecst Of Water On The Methane Hydrate Formation And Dissociation With Hollow Silica And Activated Carbon, Sarocha Rungrussamee
Effecst Of Water On The Methane Hydrate Formation And Dissociation With Hollow Silica And Activated Carbon, Sarocha Rungrussamee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The porous materials, hollow silica (HSC) and activated carbon (AC), were selected to investigate their effects with water on methane hydrate formation and dissociation. The methane hydrate formation with the porous materials was conducted at 8 MPa and 277 K. The dissociation of hydrates was achieved by thermal stimulation with 294 K temperature driving force. The result showed that the hydrate formation of the system with 1:14 HSC to water ratio, the system with excess water, provided the highest methane consumed and water conversion to hydrates. That is because the HSC has low density allowing it to float on water …
Heat Exchanger Network Design/Retrofit With Partitioning Technique For Linearization Of Specific Heat Capacity-Temperature Relation, Siwat Valeekiatkul
Heat Exchanger Network Design/Retrofit With Partitioning Technique For Linearization Of Specific Heat Capacity-Temperature Relation, Siwat Valeekiatkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Heat Exchanger Network (HEN) design has been studied for 40 years starting from heuristic technique; pinch analysis and design method to mathematical programming. The stage-wise superstructure by mathematical programming from Yee and Grossmann (1990) was one of the famous models suitable for industrial HEN design under assumption of constant average specific heat capacity (Cp) which generally should be fitted by empirical form of cubic equation. Zhu and Asante (1999) and Ayotte-Sauvé et al. (2017) used piece-wise linearization called stream segment model, to approximate Cp. Their Cp approximation techniques used high number of piece-wises to calculate Cp accurately. This paper presents …
Use Of Binary Surfactant Formulations In Low Ift Foam And Surfactant Flood, Sorrawit Tantipalakul
Use Of Binary Surfactant Formulations In Low Ift Foam And Surfactant Flood, Sorrawit Tantipalakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Viscous fingering and early breakthrough are the main problems observed during the water flooding. These problems could be overcome by using foam flooding by coinjection of surfactant solution and nitrogen gas as a mobility control in a porous media to help improve the sweep efficiency. To gain the maximum benefits of foam flooding, ultra-low interfacial tension foam was studied to obtain a foaming system with high sweep efficiency and at the same time high oil solubilization to help mobilize the oil phase from reservoir rock. In this work, mixed surfactant systems between sodium dioctylsulfosuccinate (AOT) and internal olefin sulfonate (IOS) …
Conversion Of N-Pentane To Aromatics: Effect Of Surface Modification By Chemical Liquid Deposition And Promoter Over Nano Scale Ga/Hzsm-5, Sukkatad Sintapanin
Conversion Of N-Pentane To Aromatics: Effect Of Surface Modification By Chemical Liquid Deposition And Promoter Over Nano Scale Ga/Hzsm-5, Sukkatad Sintapanin
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work studied the effects of chemical liquid deposition, i.e., TEOS concentration and multicycle silylation on Ga/HZSM-5 on their catalytic performance in aromatization of n-pentane. The parent nano scale HZSM-5 zeolite catalysts were incorporated with Ga by impregnation method followed by silylation via chemical liquid deposition (CLD) using tetraethyl orthosilicate (TEOS) by varying concentrations and number of cycles. Moreover, the small amount of Pt, Zn, La and P was introduced by co-impregnation method to study the effect of promoter. The physical and chemical properties of catalysts were characterized by N2 physisorption, XRD, NH3-TPD, IPA-TPD, TPO, TPR, SEM and 27Al MAS …
Development Of Lcsoft As A Tool For Life Cycle Assessment Of Environmental Impacts : Incorporating Additional Lcia Methodologies And Environmental Footprint, Tanathip Rattanatum
Development Of Lcsoft As A Tool For Life Cycle Assessment Of Environmental Impacts : Incorporating Additional Lcia Methodologies And Environmental Footprint, Tanathip Rattanatum
Chulalongkorn University Theses and Dissertations (Chula ETD)
Life Cycle Assessment (LCA) is a technique to calculate, assess, and analyze environmental impacts through the entire life cycle of products. LCSoft has been continuously developed as LCA software which has ability to integrate with other software e.g. process simulation software and economic analysis software. In addition, LCSoft has several functions which can analyse various environmental effects such as sensitivity analysis, alternative comparison, and eco efficiency analysis. In this thesis, several features were added into LCSoft to cover a wider application range from users and more industrial technologies. This thesis consists of four main parts. First, adding more essential equipment …