Polymer Science Commons^™

Assisted Methane Hydrate Formation With The Addition Of Promoters, Chutikan Jaikwang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Natural gas hydrates play an important role in the largest reservoir of hydrocarbons on earth. The gas hydrates have received increasing attention in an excellent way of new technology for gas in large quantity storage and transportation. However, the main challenge to use methane hy¬drates has faced many challenges such as the slow formation rate, low growth rate during hydrate formation, and low conversion ratio of gas to solid hydrates leading to poor storage capacity. In this work, methane hydrate formation and dissociation in the presence of different Cyclopentane (CP), Tetra-n-butyl phosphonium bromide (TBPB) and Tetra-n-butyl ammonium bromide (TBAB) concentrations …

Effects Of Bead Size And Concentration Of Unstable Asphaltenes Obtained From Different Centrifugation Techniques On Asphaltene Deposition In Packed Bed Apparatus, Kimchhay Lao

Chulalongkorn University Theses and Dissertations (Chula ETD)

Asphaltenes are the heaviest and most polar fraction of petroleum crude oil. They are the collection of components that can be soluble in aromatics solvents such as benzene or toluene, but insoluble in normal alkanes, n-pentane, n-hexane, or n- heptane. Asphaltenes are a class of molecules consisted of grouped aromatic rings with alkane chains. Changing pressure, temperature, composition, and shear rate during transportation can cause precipitation and deposition, resulting in reduced reservoir productivity due to restricted flow lines, fouling and blockages in the pore spaces of the reservoir. The goal of this investigation is to assess validity of two aspects …

Study On Energy Storage Ability Of Zno/Tio2 For Photocatalytic Degradation Of Isopropanol, Ratchawan Jarumanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

The photocatalytic degradation of isopropanol under UV irradiation was studied by using p-n junction of ZnO/TiO2 photocatalysts prepared by sol-gel technique. Their energy storage ability was tested with their photocatalytic activity where there was no UV illumination. That was investigated by illumination the system with UV light for 2 h and off for 2 h until 8 h. The composition and surface structure of the catalyst were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), surface area analysis, and particle size analysis. The change in the isopropanol concentration was observed by using gas chromatography. The result showed that the …

Microemulsion Formation Of Vegetable Oils Using Mixed Extended Surfactant For Cleaning Applications, Siriluk Jariyawattanarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Some vegetable oils and animal fats can form semi-solid crystalline. The formation of semi-solid fats or waxy soils results in weak interactions between the oil and surfactant during the cleaning process. In this study, the anionic extended surfac-tant (C14-15, 8PO-SO4) systems were employed to form a middle phase microemul-sion with various vegetable oils (coconut, palm and soybean oil). The addition of nonionic extended surfactant (C16-18, 2PO-4EO-OH) in the mixed surfactant systems was also evaluated to observe the solubility enhancement of oil and water phase. The IFT value of formulated surfactant systems was measured to determine the optimum salinity. The Hydrophilic-Lipophilic …

Improvement Of Life Cycle Assessment Software And Its Applications, Yodsathorn Chavewanmas

Chulalongkorn University Theses and Dissertations (Chula ETD)

LCSoft is Life Cycle Assessment (LCA) software which developed for perform LCA together with process design. It is a stand-alone tool with ability to be integrated with other process design tools such as process simulation software (PROII/ASPEN), economic analysis tool (ECON), and sustainable process design tool (SustainPro). In addition, several optional interpretation features are available such as, sensitivity analysis, alternative comparison, and eco-efficiency evaluation. In this research, LCSoft had been improved in performance and application range. The development framework consisted of four tasks. The first task deals with improvement of LCI and LCIA calculation which new pathway for calculation and …

A Quartz Crystal Microbalance Study Of Thiol:Ene Poly(Ionic Liquid) Polymerization And Gas Absorption, Yueming Wu

Murray State Theses and Dissertations

ABSTRACT

The polymerization process of, and gas absorption by, imidazolium-containing thiol:ene poly (ionic liquid)s (PILs), prepared from bisallylimidazolium bis(trifluoromethyl sulfonyl)imide [NTf₂^-] and pentaerythritoltetrakis(3 mercaptopropionate), was studied. The thiol:ene PILs examined were recently reported by groups at Murray State University. The advantage of thiol:ene PILs over other reported PILs is that thiol:ene polymers are made rapidly by UV exposure and exhibit high mechanical and thermal stability due to high cross-linking. The properties of interest for the thiol:ene PILs were studied using a quartz crystal microbalance (QCM). QCM techniques are based on the piezoelectric effect, where certain crystals (e.g., …

Green Thermosetting Factory: Novel Star-Shaped Bio-Based Systems And Their Thermosetting Resins; Synthesis And Characterization, Arash Jahandideh

Electronic Theses and Dissertations

Increasing attentions toward sustainable development, economic and environmental issues have led to many attempts at replacing the petroleum-based materials with renewables. Substitution of petroleum-based platforms with green alternative technologies is beneficiary in different ways. Using bio-renewables reduces the dependency of the national plastic industry to the petroleum resources and substantially promotes the environmental profile and sustainability of the product. It is expected that the emergence of the corn-based thermosetting industry generates substantial profits for the corn production sector. Developments in the emerging biobased thermosets are spectacular from a technological point of view. However, there are still several disadvantages associated with …

Uses For Graphene, Marcus R. Schmidt

Natural Sciences Student Research Presentations

This slide presentation for the Natural Sciences Poster Session at Parkland College discusses graphene, which is a chemically or mechanically produced single layer of pure carbon atoms. The thinnest compound known to man is also one of the strongest, with uses in technology and the health industry from faster charging batteries to motorcycle helmets. The remaining slides summarize a process by which free radicals are reduced in graphene by being treated with butyl acrylate polymerization.

Adsorptive Bubble Separation For Oil Removal, Paweena Kanokkarn

Chulalongkorn University Theses and Dissertations (Chula ETD)

This present work emphasized on the current knowledge regarding (i) feasibility of multi-stage forth flotation operation for oil removal, and (ii) comprehension of dynamic surface tensions of surfactant solutions in relation to foam characteristics. A multi-stage forth flotation efficiency depends on the enhancement of interfacial adsorption and the number of bubble caps and tray. The operational parameters including foam height, air flow rate and feed flow rate were controlled to obtain the optimum process performance. Under the optimum conditions—a number of trays of 4, a foam height of 60 cm, an air flow rate of 40 L/min, a feed flow …

Synthesis And Characterization Of Poly(Simvastatin) - Incorporated Copolymers And Blends For Bone Regeneration, Theodora Asafo-Adjei

Theses and Dissertations--Biomedical Engineering

Common biodegradable polyesters such as poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) and poly(ε-caprolactone) (PCL) are used as drug delivery vehicles for tissue regenerative applications. However, they are typically bioinert, with drug loading limitations. Polymerizing the active agent or precursor into its respective biodegradable polymer would control drug loading via molar ratios of drug to initiator used for synthesis. Simvastatin was chosen due to its favorable anti-inflammatory, angiogenic, and osteogenic properties. In addition, its lactone ring lends itself to ring-opening polymerization and, consequently, the synthesis of poly(simvastatin) with controlled simvastatin release.

Simvastatin was first polymerized with a 5kDa methyl-terminated poly(ethylene glycol) …

Tunable Nanocomposite Membranes For Water Remediation And Separations, Sebastián Hernández Sierra

Theses and Dissertations--Chemical and Materials Engineering

Nano-structured material fabrication using functionalized membranes with polyelectrolytes is a promising research field for water pollution, catalytic and mining applications. These responsive polymers react to external stimuli like temperature, pH, radiation, ionic strength or chemical composition. Such nanomaterials provide novel hybrid properties and can also be self-supported in addition to the membranes.

Polyelectrolytes (as hydrogels) have pH responsiveness. The hydrogel moieties gain or lose protons based on the pH, displaying swelling properties. These responsive materials can be exploited to synthesize metal nanoparticles in situ using their functional groups, or to immobilize other polyelectrolytes and biomolecules. Due to their properties, these …

Vegetable Oil Based Microemulsion Biofuels, U-Larak Peson

Chulalongkorn University Theses and Dissertations (Chula ETD)

The growth of energy demand increases dramatically which has resulted in an increase of exhaust emissions to air quality deterioration. Therefore, there are driving forces in the development of renewable energy production technologies. Vegetable oils based reverse micelle microemulsions have been increased in attention for biofuel production. This work aims to formulate microemulsion biofuel containing palm oil/diesel blend as nonpolar phase, and ethanol/butanol, as a polar phase. The nonionic alcohol ethoxylate surfactant with the different numbers of EO groups, EOn (n=1, 3, 5, and 9) were selected as a stabilizing agent. A pseudo-ternary phase diagram was conducted to determine an …

Electrical Property-Investigation Of Porous Clay Heterostructures Derived From Naturally-Occurring Clay Minerals For Smart Packaging, Kornkamol Srithammaraj

Chulalongkorn University Theses and Dissertations (Chula ETD)

Porous Clay Heterostructure (PCH) is an interesting material to use as entrapping system such as ethylene scavenger, respected to its high surface area with uniform and specific pore size. PCHs have been prepared by the surfactant-directed assembly of mesostructured silica within the two-dimensional galleries of clays. Then, the PCH was synthesized within the galleries of Na-bentonite clay by the polymerization of tetraethoxysilane (TEOS) in the presence of surfactant micelles. In addition, mesoporous clay with organic-inorganic hybrid (HPCH) is modified via co-condensation reaction of TEOS with candidate conductive functional groups (thiol group) and metal loading (silver), designated as MPPCH and Ag-PCH, …

Catalytic Activity Of Cu-Ceo2zro2 For Biodiesel Production, Wasupon Wongvitvichot

Chulalongkorn University Theses and Dissertations (Chula ETD)

CeO2-ZrO2 was synthesized by co-precipitation (CZ copre) and nanocasting (MSP CZ) methods for supporting 9%wt Cu catalyst loaded by deposition-precipitation (DP) method (CuCZ copre and Cu-MSP CZ, respectively). Both CuCZ copre and Cu-MSP CZ were used in esterification reaction for biodiesel production. Structure and specific surface area of the synthesized supports and catalysts were characterized by XRD and BET tecnhiques. It was found that the specific surface area of CZ copre was less than MSP CZ support. The XRD result of CuCZ copre exhibited the diffraction peak of CuO, indicating the agglomeration of Cu species on support while that of …

Microbial Conversion Of Cellulose To Sugars By Bacterial Enzyme, Kessara Seneesrisakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work studied the conversion of lignocellulosic materials to sugars, the intermediates for bioethanol production, by a bacterial enzyme. Due to the complex structure of lignocellulose, a cellulase enzyme cannot effectively access and hydrolyse cellulose fibers. Various pretreatment processes of lignocellulose have been studied to enhance enzymatic hydrolysis to date. In this work, corncob was firstly studied for microbial pretreatment using three microorganisms including two bacterial strains of Bacillus subtilis A 002 and Cellulomonas sp. TISTR 784 and a fungal strain of Phanerochaete sordida SK7. The results showed that the microbial pretreatment with P. sordida SK7 was the most effective …

Study The Best Support For Hydrolysis Of Tiger Grass, Kurizara Sayamnikorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bioethanol, one of the outstanding biofuels, is not only a renewable bio-based resource, but also interesting to research for improving better properties of the enzyme needed in the hydrolysis process. The purpose of this work is to study how to reuse the enzyme used in the hydrolysis step for bioethanol production by immobilizing Trichoderma reesei (T.reesei) on various silica supports, namely, SBA-15, TUD-1, and MCM-48. The amount of the adsorbed enzymes was determined by UV-visible spectrophotometry. Among those studied supports, SBA-15 showed 100% enzymatic adsorption on the support owing to its larger pore diameter of 6.14 nm, which is large …

Development Of Pedot-Pss/Zeolite Composite As A Gas Sensor, Pojjawan Chanthaanont

Chulalongkorn University Theses and Dissertations (Chula ETD)

Composites with Poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonic acid), PEDOT-PSS, as the matrix containing zeolites of various Si/Al ratios in the range of 23-280 were fabricated to investigate the effect of Si/Al ratios on electrical conductivity sensitivity responses towards the target gas. The electrical conductivity responses of PEDOT-PSS/Zeolite composites were altered due to the available adsorption sites for gas molecules. The addition of zeolites to the pristine PEDOT-PSS improves the electrical conductivity sensitivity of the composites by enhancing the interaction between PEDOT-PSS and target gas. Composites with PEDOT-PSS matrix containing faujasite zeolites type Y were fabricated to investigate the effects of …

Design Of Rubber Extraction Process From Tks Dandelion, Trevor A. Cody

Williams Honors College, Honors Research Projects

A design was developed for a controlled environment agriculture 3D greenhouse to grow and harvest TKS dandelions, as well as a processing plant to extract natural rubber and inulin from the roots. The design capacity was scaled for both pilot- and full-scale production: 100 and 100,000 tonnes of natural rubber per year, respectively. The byproducts of the process were dandelion greens, inulin, cellulose, and glucose; all of these except for cellulose were able to be valorized. The greenhouse was designed based on existing 3D hydroponic growing environments, and the extraction process was designed based on the original TKS dandelion extraction …

Design Of Natural Rubber Extraction From Tks Dandelion, Jehad S. Alrawajfeh, Trevor Cody, Jason Pogozelski

Williams Honors College, Honors Research Projects

A design was developed for a controlled environment agriculture 3D greenhouse to grow and harvest TKS dandelions, as well as a processing plant to extract natural rubber and inulin from the roots. The design capacity was scaled for both pilot- and full-scale production: 100 and 100,000 tonnes of natural rubber per year, respectively. The byproducts of the process were dandelion greens, inulin, cellulose, and glucose; all of these except for cellulose were able to be valorized. The greenhouse was designed based on existing 3D hydroponic growing environments, and the extraction process was designed based on the original TKS dandelion extraction …

Characterization Of Polyurethane For Use As Substrate In Nanofiber Sensor For Biomedical Applications, Megan Theaker

Williams Honors College, Honors Research Projects

The purpose of this project is to begin to determine properties of polymer nanocomposites that make a suitable substrate for nanofiber sensors. In this work, sensitivity of a sodium ion selective sensor constructed with polyurethane was used as a benchmark for comparison with sensors constructed with nylon-6. The sensors were characterized using contact angle and chronoamperometry. Using an ANOVA analysis, the results showed that the multi-walled carbon nanotube type was a significant factor on sensor response both with and without additional functionalization of the polymer by calixarene. The weight percentage of polyurethane in the electrospinning solution was also statistically significant …