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Formation mechanism of anionic-surfactant-templated mesoporous silica (AMS)Gao, Chuanbo January 2009 (has links)
This dissertation is focused on synthesis, characterization and formation mechanism of anionic-surfactant-templated mesoporous silica (AMS). Structural control mechanisms of AMS are investigated. First, different ionization degree of anionic surfactant affected by the acidity or alkalinity of the synthesis system gives rise to different charging density of micelles and therefore determines the organic/inorganic interface curvature, producing mesophases from cage-type to cylindrical, bicontinuous and lamellar. Second, mesocage/mesocage electrostatic repulsive interaction affects the formation of cage-type mesostructure, which is derived from a full-scaled synthesis-field diagram of AMS. The mesocage/mesocage interaction changes with charge density of mesocages and gives rise to their different packing manners. Third, the structural properties of AMS materials could be tuned by molecular features of surfactant and co-structure-directing agent (CSDA). The pore size of AMS is found to be controlled by alkyl chain length, ionization degree of surfactant and the CSDA/surfactant ratio. Alkyl chain length of surfactant determines size of micelles and thus mesopores. Larger ionization degrees of anionic surfactant give rise to smaller pore sizes due to thermodynamic coiling of alkyl chains of surfactant. The hydrophobic interactions between the pendant organic groups of CSDA on the silica wall and the hydrophobic core of the micelles drive a contraction of the mesopores. A mesoporous silica with novel bicontinuous cubic Pn-3m structure has been prepared using a diprotic anionic surfactant. 3d-reconstruction of the structure shows that it is bicontinuous composed of an enantiomeric pair of 3d mesoporous networks that are interwoven with each other, divided by a D surface. Inverse replication suggests the possible presence of ordered complimentary micropores in the material.
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Multiphase, Multicomponent Systems: Divalent Ionic Surfactant Phases and Single-Particle Engineering of Protein and Polymer GlassesRickard, Deborah January 2011 (has links)
<p>This thesis presents an analysis of the material properties and phase behavior of divalent ionic surfactant salts, and protein and polymer glasses. There has been extensive interest in understanding the phase behavior of divalent ionic surfactants due to the many applications of ionic surfactants in which they come into contact with divalent ions, such as detergency, oil recovery, and surfactant separation processes. One goal of determining the phase boundaries was to explore the option of incorporating a hydrophobic molecule into the solid phase through the micelle-to-crystal bilayer transition, either for drug delivery applications (with a biologically compatible surfactant) or for the purpose of studying the hydrophobic molecule itself. The liquid micellar and solid crystal phases of the alkaline earth metal dodecyl sulfates were investigated using calorimetry, visual inspection, solubilization of a fluorescent probe, and x-ray diffraction. The Krafft temperature and dissolution enthalpy were determined for each surfactant, and partial composition-temperature phase diagrams of magnesium dodecyl sulfate-water, calcium dodecyl sulfate-water, as well as sodium dodecyl sulfate with MgCl<sub>2</sub> and CaCl<sub>2</sub> are presented. As a proof of concept, fluorescence microscopy images showed that it is, in fact, possible to incorporate a small hydrophobic molecule, diphenylhexatriene, into the solid phase.</p><p>The second, and main, part of this thesis expands on work done previously in the lab by using the micropipette technique to study two-phase microsystems. These microsystems consist of a liquid droplet suspended in a second, immiscible liquid medium, and can serve as direct single-particle studies of drug delivery systems that are formed using solvent extraction (e.g., protein encapsulated in a biodegradable polymer), and as model systems with which to study the materials and principles that govern particle formation. The assumptions of the Epstein-Plesset model, which predicts the rate of droplet dissolution, are examined in the context of the micropipette technique. A modification to the model is presented that accounts for the effect a solute has on the dissolution rate. The modification is based on the assumption that the droplet interface is in local thermodynamic equilibrium, and that the water activity in a solution droplet can be used to determine its dissolution (or dehydration) rate. The model successfully predicts the dissolution rates of NaCl solutions into octanol and butyl acetate up to the point of NaCl crystallization. The dehydration of protein solutions (lysozyme or bovine serum albumin) results in glassified microbeads with less than a monolayer of water coverage per protein molecule, which can be controlled by the water activity of the surrounding organic medium. The kinetics of dehydration match the prediction of the activity-based model, and it is shown how the micropipette technique can be used to study the effect of dissolution rate on final particle morphology. By using a stable protein with a simple geometry (lyosyzme), this technique was be used to determine the distance dependence of protein-protein interactions in the range of 2-25 Å, providing the first calculation of the hydration pressure decay length for globular proteins. The distance-dependence of the interaction potential at distances less than 9 Å was found to have a decay length of 1.7 Å, which is consistent with the known decay length of hydration pressure between other biological materials. Biodegradable polyesters, such as poly(lactide-co-glycolide) (PLGA), are some of the most common materials used for the encapsulation of therapeutics in microspheres for long-term drug release. Since they degrade by hydrolysis, release rates depend on water uptake, which can be affected by processing parameters and the material properties of the encapsulated drug. The micropipette technique allows observations not possible on any bulk preparation method. Single-particle observations of microsphere formation (organic solvent extraction into a surrounding aqueous phase) show that as solvent leaves the microsphere and the water concentration in the polymer matrix becomes supersaturated, water phase separates and inclusions initially grow quickly. Once the concentration in the polymer matrix equilibrates with the surrounding aqueous medium, the water inclusions continue to grow due to dissolved impurities, solvent, and/or water-soluble polymer fragments resulting from hydrolysis, all of which locally lower the water activity in the inclusion. Experiments are also presented in which glassified protein microbeads were suspended in PLGA solution prior to forming the single microspheres. This technique allowed the concentration of protein in a single microbead/inclusion to be determined as a function of time.</p> / Dissertation
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A study of Nanofilled Silicone Dielectrics for Outdoor InsulationRamirez Vazquez, Isaias January 2009 (has links)
Polymeric insulators are now a common replacement for conventional porcelain and glass string insulators on overhead distribution and transmission lines. The use of this mature technology represents many advantages to the utilities; however, in polluted environments and those with high moisture levels in the environment, electrical discharges will develop on the surface of the insulation. In the long term, electrical discharges cause degradation of the polymer insulation in the form of electrical tracking and material erosion, and both are detrimental to the life of the insulation. Inorganic fillers are added to polymer materials to make the insulation more resistant to discharges, and at the same time, to lower the cost of the insulation. However, there is a limit to the amount of filler that can be added as the processability of the polymer compound becomes extremely difficult and expensive. Microfillers are extensively used to modify the physical properties of the polymeric matrix, and the properties of these composites are well known. On the other hand, nanofillers are being used in some insulating composites for reinforcement of mechanical properties; their electrical characteristics have shown inconsistency in the literature, and this is attributable to the non-uniformity of the filler dispersion. Most researchers agree that particle dispersion is critical in the development of nanocomposites for electrical insulation applications. If the nanoparticles are well dispersed, the electrical properties of these materials will be significantly improved.
The main problem in using nanofillers is that the nanoparticles agglomerate easily because of their high surface energy, such that conventional mixing techniques are unable to break apart the nanoparticle aggregates. A secondary problem is the incompatibility of the hydrophobic polymer with the hydrophilic nanoparticles which results in poor interfacial interactions.
In this thesis, the reinforcement of a silicone rubber matrix is successfully accomplished with the combination of microfiller, nanofiller, and a commercial surfactant.
To improve particle dispersion, several techniques are available apart from mixing. This includes surface modification of the nanoparticles by chemical and physical methods by using surfactants. While surfactants are commonly applied to liquids, their use to disperse nanoparticles in compositions forming solid dielectric materials has not yet been reported. The findings in this thesis have shown that Triton X-100, a common surfactant, significantly aids in the dispersion of nanosilica and nanoalumina in silicone rubber. The main advantage of the surfactant is that it lowers the surface energy and the interfacial tension of the nanoparticles. This reduces agglomeration and facilitates the separation of the particles during mixing, thereby allowing improved dispersion of the nanofillers, as observed through Scanning Electron Microscopy (SEM). However, also shown in the thesis is that Triton X-100 cannot interact efficiently with all types of nanofillers.
A high concentration of surfactant can also compromise the adsorption of the matrix polymer chains on the filler particles, so it is necessary to establish a balance between matrix adsorption and the dispersion of the particles. Mechanical properties such as the tensile strength, elongation at break, and hardness may also suffer from the use of excess surfactant. In addition, excess surfactant can lead to surface wetting properties different from composites containing none. Better wetting due to the migration of excess surfactant to the surface of the silicone may favour arcing in a wet environment.
The current investigation shows that for a specific filler and concentration, an optimal concentration of surfactant provides good erosion resistance without adversely affecting the mechanical characteristics of the nanocomposite. Stress–strain and hardness measurements are done to investigate the surfactant’s effect on the mechanical properties of the composites. The effect of the surfactant on the surface of the composites is analyzed with static contact angle measurements.
The heat resistance of nanofilled silicone rubber is explored using an infrared laser simulating the heat developed by dry-band arcing. Also, several industry standard test methods such as salt fog and inclined plane tests are used to evaluate the erosion resistance of the filled composites. The results of all three tests confirm that the combination of microfiller and nanofiller with surfactant results in composites with improved erosion resistance to dry band arcing, with the exception of the case where calcinated filler is used in the formulation.
In this thesis, the thermal conductivity is measured using a standard ASTM method and calculated using several theoretical, semi-theoretical, and empirical models. A thermal model developed in COMSOL Multiphysics and solved using a finite element method (FEM) shows a temperature distribution in the modelled nanocomposites which is comparable to the temperature distribution measured with an infrared camera under laser heating.
In addition, this investigation aims to define the mechanism by which the nanofillers improve the heat and erosion resistance of the silicone composites. In order to understand this mechanism, nano fumed silica, nano natural silica, and nano alumina are used in a silicone rubber (SiR) matrix in order to study the thermally decomposed silicone and the residual char that is formed during laser ablation tests.
The white residue remaining after laser ablation on the surface of composites with fumed silica, natural silica, and alumina is analyzed in a number of ways. Scanning Electron Microscopy, Energy Dispersive X-ray analysis (EDAX), and X-ray diffraction (XRD) techniques are used to analyze the thermally decomposed silicone residue after laser heating indicating that the protective mechanism of the three analyzed nanofillers – fumed silica, natural silica, and alumina – appears to be the same. The formation of a continuous layer on the surface behaves as a thermal insulator protecting the material underneath from further decomposition.
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Effects of Mixed Stabilizers (Nanoparticles and Surfactant) on Phase Inversion and Stability of EmulsionsMalhotra, Varun January 2009 (has links)
Immiscible dispersions of oil and water are encountered in many industries such as food, pharmaceuticals, and petroleum. Phase inversion is a key phenomenon that takes place in such systems whereby the dispersed phase and the continuous phase invert spontaneously. Stabilizers such as surfactants or solid nanoparticles have been used in the past to improve the stability of emulsions. However, the combined effects of surfactants and nanoparticles on phase inversion and stability of oil and water emulsions have not been studied.
This study investigates the synergistic effects of silica nanoparticles (of varying hydrophobicities) and non-ionic surfactant on phase inversion of water-in-oil emulsion to oil-in-water emulsion. The effect of oil viscosity on phase inversion phenomenon is also studied. Stabilizers were initially dispersed in the oil phase with the help of a homogenizer. The water concentration of the system was gradually increased while maintaining the mixing. Online conductivity measurements were carried out to obtain the phase inversion point. Experimental results on the effects of pure stabilizers (either silica nanoparticles or surfactant) and mixed stabilizers (combined silica nanoparticles and surfactant) on phase inversion of emulsions are presented. The stability of these emulsions is also investigated.
From the results obtained in this study it is clear that catastrophic phase inversion phenomenon and stability of water-in-oil emulsions can be controlled with the help of different stabilizers. In order to extend the critical dispersed phase volume fraction at which phase inversion occurs surfactant type stabilizer was found to be more effective than solid nanoparticles. On the other hand, emulsion stability was mainly dominated by solid nanoparticles. The hybrid of the two stabilizers and its effect on phase inversion and stability are discussed in the thesis.
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Investigation on using Supercritical Carbon Dioxide as Desorbing and Reaction Medium in the Surfactant Production ProcessYuan, Yuanping January 2007 (has links)
To date, an estimated 70% of energy consumed comes from fossil fuels, such as coal, oil and natural gas. The major source of sulfur dioxide (SO2) emissions comes from
combustion of these fossil fuels. Sulfur dioxide is a significant pollutant, because it and its higher oxidation product (SO3) react with moisture in the atmosphere to produce sulfuric acid. This results in acid rain, which comes back to earth and affects people, animals, and vegetation. Therefore, the governments of Canada, US and European
countries are issuing stricter and stricter regulation to control SO2 emissions.
In conventional SO2 removal processes, lime or limestone scrubbers are used, but they
require large amounts of water and enough landfill sites to deal with the solid wastes. Previous attempts were made in our laboratory to recover SO2 adsorbed on activated carbon to produce sulfuric acid using non-aqueous solvents. Unfortunately, in this adsorption/distillation process, the SO2 recovery was low, as was the quality of sulfuric acid, that could not be marketable. The topic of this thesis was then conceived as an attempt to first recover SO2 via SO3 formation using supercritical carbon dioxide instead
of water or non-aqueous flushing agents (desorption step) and then to use the recovered SO3 to produce linear alkylbenzene sulfonates (LAS), the main component of detergent.
In the adsorption and oxidation experiments of this project, charcoal activated carbon
(AC) was used to adsorb SO2 and to catalyze SO2 oxidation. The process started with a
simulated flue gas, 3500 ppm SO2, 5% O2, balanced with N2. When the simulated flue
gas passed through the activated carbon bed reactor, more than 95% of SO2 was oxidized
to SO3.
In the desorption process, SO3 contacted with the AC bed was removed using supercritical carbon dioxide (SCCO2) and 95% sulfur removal was achieved at
appropriate operating conditions, for example, for a carbon bed preheated at 250°C for 6 h, and flushed by recycled SCCO2.
The LAS production experiments consisted in reacting liquid linear alkylbenzene (LAB)
with the recovered SO3 in an absorption column. Ceramic filters and glass beads were
used in the absorption columns to break up the gas bubbles and increase the contact time between the gas and the liquid absorbent. When staged pressure columns were used and when LAB was heated to 40°C, nearly 95% of SO3 reacted with LAB to produce LAS.
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A study of Nanofilled Silicone Dielectrics for Outdoor InsulationRamirez Vazquez, Isaias January 2009 (has links)
Polymeric insulators are now a common replacement for conventional porcelain and glass string insulators on overhead distribution and transmission lines. The use of this mature technology represents many advantages to the utilities; however, in polluted environments and those with high moisture levels in the environment, electrical discharges will develop on the surface of the insulation. In the long term, electrical discharges cause degradation of the polymer insulation in the form of electrical tracking and material erosion, and both are detrimental to the life of the insulation. Inorganic fillers are added to polymer materials to make the insulation more resistant to discharges, and at the same time, to lower the cost of the insulation. However, there is a limit to the amount of filler that can be added as the processability of the polymer compound becomes extremely difficult and expensive. Microfillers are extensively used to modify the physical properties of the polymeric matrix, and the properties of these composites are well known. On the other hand, nanofillers are being used in some insulating composites for reinforcement of mechanical properties; their electrical characteristics have shown inconsistency in the literature, and this is attributable to the non-uniformity of the filler dispersion. Most researchers agree that particle dispersion is critical in the development of nanocomposites for electrical insulation applications. If the nanoparticles are well dispersed, the electrical properties of these materials will be significantly improved.
The main problem in using nanofillers is that the nanoparticles agglomerate easily because of their high surface energy, such that conventional mixing techniques are unable to break apart the nanoparticle aggregates. A secondary problem is the incompatibility of the hydrophobic polymer with the hydrophilic nanoparticles which results in poor interfacial interactions.
In this thesis, the reinforcement of a silicone rubber matrix is successfully accomplished with the combination of microfiller, nanofiller, and a commercial surfactant.
To improve particle dispersion, several techniques are available apart from mixing. This includes surface modification of the nanoparticles by chemical and physical methods by using surfactants. While surfactants are commonly applied to liquids, their use to disperse nanoparticles in compositions forming solid dielectric materials has not yet been reported. The findings in this thesis have shown that Triton X-100, a common surfactant, significantly aids in the dispersion of nanosilica and nanoalumina in silicone rubber. The main advantage of the surfactant is that it lowers the surface energy and the interfacial tension of the nanoparticles. This reduces agglomeration and facilitates the separation of the particles during mixing, thereby allowing improved dispersion of the nanofillers, as observed through Scanning Electron Microscopy (SEM). However, also shown in the thesis is that Triton X-100 cannot interact efficiently with all types of nanofillers.
A high concentration of surfactant can also compromise the adsorption of the matrix polymer chains on the filler particles, so it is necessary to establish a balance between matrix adsorption and the dispersion of the particles. Mechanical properties such as the tensile strength, elongation at break, and hardness may also suffer from the use of excess surfactant. In addition, excess surfactant can lead to surface wetting properties different from composites containing none. Better wetting due to the migration of excess surfactant to the surface of the silicone may favour arcing in a wet environment.
The current investigation shows that for a specific filler and concentration, an optimal concentration of surfactant provides good erosion resistance without adversely affecting the mechanical characteristics of the nanocomposite. Stress–strain and hardness measurements are done to investigate the surfactant’s effect on the mechanical properties of the composites. The effect of the surfactant on the surface of the composites is analyzed with static contact angle measurements.
The heat resistance of nanofilled silicone rubber is explored using an infrared laser simulating the heat developed by dry-band arcing. Also, several industry standard test methods such as salt fog and inclined plane tests are used to evaluate the erosion resistance of the filled composites. The results of all three tests confirm that the combination of microfiller and nanofiller with surfactant results in composites with improved erosion resistance to dry band arcing, with the exception of the case where calcinated filler is used in the formulation.
In this thesis, the thermal conductivity is measured using a standard ASTM method and calculated using several theoretical, semi-theoretical, and empirical models. A thermal model developed in COMSOL Multiphysics and solved using a finite element method (FEM) shows a temperature distribution in the modelled nanocomposites which is comparable to the temperature distribution measured with an infrared camera under laser heating.
In addition, this investigation aims to define the mechanism by which the nanofillers improve the heat and erosion resistance of the silicone composites. In order to understand this mechanism, nano fumed silica, nano natural silica, and nano alumina are used in a silicone rubber (SiR) matrix in order to study the thermally decomposed silicone and the residual char that is formed during laser ablation tests.
The white residue remaining after laser ablation on the surface of composites with fumed silica, natural silica, and alumina is analyzed in a number of ways. Scanning Electron Microscopy, Energy Dispersive X-ray analysis (EDAX), and X-ray diffraction (XRD) techniques are used to analyze the thermally decomposed silicone residue after laser heating indicating that the protective mechanism of the three analyzed nanofillers – fumed silica, natural silica, and alumina – appears to be the same. The formation of a continuous layer on the surface behaves as a thermal insulator protecting the material underneath from further decomposition.
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Effects of Mixed Stabilizers (Nanoparticles and Surfactant) on Phase Inversion and Stability of EmulsionsMalhotra, Varun January 2009 (has links)
Immiscible dispersions of oil and water are encountered in many industries such as food, pharmaceuticals, and petroleum. Phase inversion is a key phenomenon that takes place in such systems whereby the dispersed phase and the continuous phase invert spontaneously. Stabilizers such as surfactants or solid nanoparticles have been used in the past to improve the stability of emulsions. However, the combined effects of surfactants and nanoparticles on phase inversion and stability of oil and water emulsions have not been studied.
This study investigates the synergistic effects of silica nanoparticles (of varying hydrophobicities) and non-ionic surfactant on phase inversion of water-in-oil emulsion to oil-in-water emulsion. The effect of oil viscosity on phase inversion phenomenon is also studied. Stabilizers were initially dispersed in the oil phase with the help of a homogenizer. The water concentration of the system was gradually increased while maintaining the mixing. Online conductivity measurements were carried out to obtain the phase inversion point. Experimental results on the effects of pure stabilizers (either silica nanoparticles or surfactant) and mixed stabilizers (combined silica nanoparticles and surfactant) on phase inversion of emulsions are presented. The stability of these emulsions is also investigated.
From the results obtained in this study it is clear that catastrophic phase inversion phenomenon and stability of water-in-oil emulsions can be controlled with the help of different stabilizers. In order to extend the critical dispersed phase volume fraction at which phase inversion occurs surfactant type stabilizer was found to be more effective than solid nanoparticles. On the other hand, emulsion stability was mainly dominated by solid nanoparticles. The hybrid of the two stabilizers and its effect on phase inversion and stability are discussed in the thesis.
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Removal of DDT from Soil using Combinations of SurfactantsRios, Luis Eglinton 17 May 2010 (has links)
Organochlorine pesticides (OCPs) were used in agriculture throughout the world for a long time because they are very effective for pest control, but OCPs such as DDT and its metabolites can threaten human health and ecological systems. Although DDT has been banned for use in Canada since 1972, it still persists in Canadian farmland at detectable levels due to its chemical stability. The soils contaminated with DDT require economical remediation strategies because of the low land value and rural location.
Although soil washing has been proposed as a possible economical technique to remove DDT, it has very low water solubility and so it is necessary to consider using surfactants to improve the soil-washing process. Building on previous research, we hypothesize that combinations of surfactants can be used to improve the performance of this remediation method.
The surfactants Tween 80, Brij 35, and sodium dodecylbenzene sulfonate (SDBS) were selected based on environmental and reported performance criteria. Combinations of surfactants were tested in both batch and leaching column experiments. Experiments indicated that removal efficiency and flowrate in leaching columns were optimized when a mixture of 2% Brij 35 and 0.1% SDBS was employed. The presence of Tween 80 was found to be less effective, possibly due to its higher biodegradability in the soil.
Since the measurement of surfactant concentration in the wash solution is important, several methods were tested before finally selecting a simple COD analysis as a surrogate parameter. Using the COD analysis, partitioning experiments were performed to measure the adsorption of surfactant on the soil. For economic reasons, it would be desirable to reuse the surfactant in a washing process. For this purpose, we employed activated carbon to selectively remove the more hydrophobic DDT from the surfactant solutions. Preliminary results have shown that carbon adsorption can remove some DDT, but additional work is required to understand and optimize the process.
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Characterization of Mineral Oil, Coal Tar and Soil Properties and Investigation of Mechanisms That Affect Coal Tar Entrapment in and Removal from Porous MediaKong, Lingjun 12 July 2004 (has links)
Mineral oils and coal tars are complex nonaqueous phase liquids (NAPLs), which can serve as long-term sources of ground water contamination. Very limited data are available on mineral oil and coal tar entrapment in and removal from porous media. Thus, the objectives of this research were to evaluate the behavior of these NAPLs in porous media, and investigate the mechanisms governing NAPL entrapment in and recovery from porous media.
Quantification of properties of three commercial mineral oils and six MGP coal tars reveals that mineral oils are slightly viscous LNAPLs (density: ~0.88 g/cm3; viscosity: 10-20 cP), whereas coal tars are highly viscous DNAPLs (density: 1.052-1.104 g/cm3; viscosity: 32-425 cP). Measured oil (tar)-water interfacial tensions (IFT) were lower than that of pure NAPLs. Properties of 16 field soil samples (soil particle size distribution, specific surface area, total carbon content, cationic exchange capacity and soil moisture release curves) were characterized. Correlations between residual NAPL saturation and NAPL and soil properties were developed, and show that the entrapment of NAPL dependent upon soil particle size distribution, total carbon content, NAPL viscosity and NAPL-water IFT.
Aqueous pH and ionic strength were found to influence the interfacial properties in tar-water-silica systems. At pHs greater than 7.0, observed reduction in contact angle were attributed to the repulsive electrostatic force between coal tar and solid surface. When pH less than 4, hydration forces played a role on the contact angle decrease. The IFT reduction was resulted from the accumulation of surface-active molecules at the tar-water interface. The effect of ionic strength on interfacial properties was not significant below 0.5 M.
The effects of temperature and surfactant or surfactant/polymer addition on coal tar removal was investigated by conducting coal tar displacement experiments at three different temperatures (22, 35, and 50??with sequential flushing of water, surfactant and surfactant/polymer. Coal tar removal from porous media was enhanced by elevating temperature and surfactant flushing due to the viscosity and IFT reduction, respectively. Xanthan gum was used as the polymer to increase the viscosity of the displacing fluid. In summary, these results provide tools for the prediction of NAPL entrapment in porous media, and for the selection of remediation strategies for coal tar contaminated source zone.
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Sediment Pollution Investigation and Processing Technology Assessment of Kaohsiung Harbor, TaiwanChen, Chun-Ting 19 June 2012 (has links)
This study focuses on the Kaohsiung industrial pier sediment survey, assessment and feasibility study of the approach. In this study, field monitoring operations, including the close Salt Water River mouth area of the industrial port (area A), the far Salt Water River mouth area of the industrial port (area B) and for the factories and shipyards at the junction of the terminal area (area C), The sampling of sediments of three core and three surface sediments of area A that used as treating test at laboratory.
The survey results show that the industrial pier some heavy metals in the sediment concentration is higher than the quality indicators in the sediment above the limit (ULV), especially copper and zinc. In addition, the concentration of heavy metals of industrial pier area A, B and C of the sediment at least one of them is than current soil control standard. Among them, the frequency of exceeding control standards of copper concentration is the highest, the surface sediments of area A, B and C were about 75%, 42% and 0% respectively, while the core sediments were about 20%, 90% and 15%. These results indicate that the industrial pier sediment required to carry out appropriate pre-treatment to reclamation land to recycling. After investigation, simulation and estimation, the required appropriate treatment sediment in order to landfill volume of industrial pier area A and B (Salt Water River mouth) were approximately 40,000 and 36,400 cubic meters, the total approximately 76,400 cubic meters. Industrial pier is located in the Salt Water River mouth, and therefore withstand the effects of pollutants of the upstream sources flowed in, and than the sediment quality was poor. Sediments were accumulated in the bottom should be removed and sediments at the upstream Salt Water River should be treated too, the remediation and pollution source control for the future to improve the sediment quality is the most important work in Taiwan.
In this study, chemical washing and chemical oxidation of the two treatment technology for industrial pier sediment organic pollutants (total petroleum hydrocarbons (TPH) as the target pollutants) to deal with the feasibility test. Sediment to be processed was collected neart the industrial pier, the pH value of approximately 7.1, the moisture content was 43.9%, 20.1% organic matter content, while the particle size composition of mainly fine particles (silt + clay) to about 84.3% handling may be more difficult. The sediments of the TPH concentration of 8,691 mg / kg. Three surfactants Simple Green (SG), Triton X-100 (TX-100) and Tween 80 (TW80) were used at sediment washing test,washing with 60 pv and 5% (v / v) SG could remove 97.3% TPH at the end of the mud; 0.5% (v / v) TX-100 could remove 96.8% TPH; washing with 30 pv, 1% (v / v) TX-100 could remove 94.6% the TPH; washing with 10 pv, 5% (v / v) TX-100 could remove 96.7% TPH; but TW80 leaching ineffective. Oxidation processing, applied 6% H2O2 reaction 180 min, 58.2% of TPH could be removed. Connection of washing and oxidation treatment process, could be removed total of 86% of TPH. The sediment surface morphology before and after treatment were observed by SEM were not significantly different, no surfactant emulsion was left at sediment after treated, this result revealed the connection of washing and oxidation treatment process could remove most of TPH and less harmful to the environment was an available technique.
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