none

A transverse gas flow TEA C0₂ laser has been constructed and the use of a perforated hollow rod to serve simultaneously as the cathode of the discharge and the gas inlet vessel was successfully demonstrated. The electrical efficiency of the laser is typically 3% with peak powers of 40 kw being emitted on the P(20), P(18) and P(16) lines of the C0₂ spectrum. A parametric study of peak power, gas pressure, gas composition, time delay of the laser pulse and the interdependence of these quantities was undertaken. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

With increasing oil prices and attention towards the reduction of anthropogenic CO2, the use of supercritical carbon dioxide for Fischer Tropsch Synthesis (FTS) is showing promise in fulfilling the demand of clean liquid fuels. The evidence of consumption of carbon dioxide means that it need not to be removed from the syngas feed to the Fischer Tropsch reactor after the gasification process. Over the last five years, research at SIUC have shown that FTS in supercritical CO2 reduces the selectivities for methane, enhances conversion, reduces the net CO2 produces in the coal to liquid fuels process and increase the life of the catalyst. The research has already evaluated the impact of various operating and feed conditions on the FTS for the once through process. We believe that the integration of unreacted feed recycle would enhance conversion, increase the yield and throughput of liquid fuels for the same reactor size. The proposed research aims at evaluating the impact of recycle of the unreacted feed gas along with associated product gases on the performance of supercritical CO2 FTS. The previously identified conditions will be utilized and various recycle ratios will be evaluated in this research once the recycle pump and associated fittings have been integrated to the supercritical CO2 FTS. In this research two different catalysts (Fe-Zn-K, Fe-Co-Zn-K) were analyzed under SC-FTS in different recycle rate at 350oC and 1200 psi. The use of recycle was found to improve conversion from 80% to close to 100% with both catalysts. The experiment recycle rate at 4.32 and 4.91 was clearly surpassing theoretical recycle curve. The steady state reaction rate constant was increased to 0.65 and 0.8 min-1 for recycle rate of 4.32 and 4.91 respectively. Carbon dioxide selectivity was decreased for both catalyst as it was converting to carbon monoxide. Carbon dioxide consumption was increased from 0.014 to 0.034 mole fraction. This concluded that CO2 is being used in the system and converting which created the concentration of the feed gas higher inside the reactor. The research has provided the best conditions for the enhanced conversion while minimizing CO2 formation. Though this research was not able to provide the optimal recycle rate it have created the path for the future research to proceed in the right direction. This reduction and utilization of CO2 will help to reduce the cost of carbon dioxide removal and saves the environment from carbon dioxide emission.

Introduction Recently in our laboratory we needed a reliable and relatively simple source of aqueous solutions of [11C]CO2. We examined various methods of trapping [11C]CO2 gas both in solution and on ion exchange resins, followed by elution into aqueous phase. We favor simple methods that have high trapping and elution efficiencies and produce a highly concentrated solution. Furthermore, we desired methods that would minimize the use of hazardous reagents and materials with respect to both handling and disposal. We also considered the formulation of the final solution in terms of chemical compatibility with contacted materials, working with the assumption that dilute bicarbonate or carbonate solutions will have little reactivity with many materials. In a phantom, compatibility with materials (i.e. plastics, glues, metals, etc.) is important (1-4), while in (bio)geochemical studies – where transport of carbon is important – the chemical form of the radiolabelled molecule is important, but compatibility must be determined on a case-by-case basis (5-7). Small medical cyclotrons can easily produce carbon-11 as gaseous [11C]CO2, and various methods are utilized to incorporate carbon-11 into solution, often with unfavorable resource requirements, costs, or chemical properties. Commonly [11C]CO2 gas is bubbled through a strong base, forming the carbonate anion; but neutralizing a strong base (as to avoid special handling or disposal requirements) requires a large volume of diluent or buffer; or a very precise addition of acid – which if done improperly – may lead to an acidic pH and subsequent loss of [11C]CO2 from solution (8,9). Alternatively, [11C]CO2 (or [11C]CH4) can be converted to [11C]CH3I at high-yield, but requires specialized, expensive radio-synthesis equipment (10-12). [11C]CH3I can then be trapped in DMSO (albeit providing a volatile and hazardous solution) or used as a synthon en route to water soluble compounds such as [11C]choline (13). Finally, leftover radiolabelled radiopharmaceuticals from a carbon-11 imaging experiment could be used, but chemical compatibility (i.e. lipophilicity) of the radiolabelled compound may be of concern. Carbon dioxide gas will dissolve with a solubility of 1.5 g/L at STP (9) and slowly react with water to generate carbonic acid (H2CO3), a weak acid. Passing [11C]CO2 through a base-activated ion exchange cartridge, the [11C]CO2 reacts with hydroxide ions to form [11C]carbonate which is bound to the resin due to its higher selectivity for carbonate than hydroxide (14). Elution with excess bicarbonate displaces [11C]carbonate and neutralizes any remaining hydroxide, providing a 11C aqueous solution that is mildly basic, chemically non-hazardous, and very concentrated. Material and Methods [11C]CO2 gas trapping efficiency was evaluated for solutions and base-activated ion exchange resins. The gas was delivered either rapidly in a high-flow bolus directly from the cyclotron target or slowly in a low-flow helium stream during heating of a carbosieves column. Elution efficiency of ion exchange cartridges were evaluated for both fraction of trapped activity eluted and volume of solution needed for elution. [11C]CO2 was produced via the 14N(p,α)11C reaction on a CTI RDS111 – 11 MeV cyclotron at the Lawrence Berkeley National Laboratory’s Bio-medical Isotope Facility. The 7 mL target is pressurized to 315 psi with 1% O2/N2 gas, equating to 150 mL gas at STP. For direct-from-target trapping experiments, the target was decompressed and routed to the cartridge via 50 feet of 0.020” I.D. tubing until the target falls to atmospheric pressure (~55 seconds) providing an inhomogeneous flow – a short rapid burst of flow followed by a longer low-flow bleed. For helium-eluted experiments, the [11C]CO2 was unloaded from the cyclotron target and trapped on a room-temperature carbosieves column (15). Target gases were subsequently flushed from the column for 30 seconds with helium at 50 mL/min. After heating the column to 125 °C without gas flow, [11C]CO2 was eluted off the column in helium at 15 mL/min. [11C]CO2/He was bubbled through 9 aqueous and 2 organic solutions to test for trapping efficiency in a slow, steady helium stream at 15 mL/min (sodium hydroxide (0.96M, 0.096M, 0.0096M), sodium bicarbonate (1.14M, 0.57M, 0.057M), sodium carbonate (2.0M, 1.0M, 0.10M), ethanol, and DMSO (2mL ea.). An Ascarite-filled cartridge was attached to trap any untrapped [11C]CO2. Measures of radioactivity were made using a Capintec CRC-15R dose calibrator. Trapping efficiency for solutions is calculated as the fraction of radioactivity captured in solution relative to the sum of the solution and the Ascarite trap. Three different commercially available, ion ex-change cartridges were evaluated for trapping and elution efficiencies. FIGURE 1 shows a photo-graphic comparison of the physical size and shapes of the cartridges as well as a X-ray computed tomography (CT) cross sectional view of the internal ion exchange resin volume and dead volume of the cartridges. All cartridges were activated with 1 mL of 1 N aqueous NaOH followed by passing 10 mL deionized water then 10 mL of air through the cartridge. In both direct-from-target (n = 4) and helium-stream experiments (n = 3 or 4), cartridges were connected to [11C]CO2 delivery lines via Luer connections. The gas exiting the cartridge passed through an empty 3 mL crimp-top vial as a liquid trap en route to an Ascarite trap on the vent needle as described above. Trapping efficiency for cartridges is calculated as the fraction of radioactivity captured on the cartridge relative to the sum of the cartridge, the empty vial, and the Ascarite trap. Cartridges were eluted with 0.5 mL of saturated sodium bicarbonate solution (1.14 M @ 20°C) followed by 9.5 mL water and 10 mL air. Elution efficiency is calculated as the fraction of radioactivity eluted in 10 mL relative to the sum of the spent cartridge following elution and the 10 mL eluate (Equation 5). The pH of the eluate was measured using 0-14 pH test strips. Results and Conclusion The trapping of [11C]CO2 in all solutions was less than 70% of the total radioactivity with the exception of the 0.96 M and 0.096 M NaOH. With a higher concentration of base driving equilibrium towards carbonate stability, it could be expected that the most basic solution had the best trapping efficiency, but this attribute also means it is least desirable solution to work with from a hazardous material or chemical compatibility perspective. When [11C]CO2 was delivered in a helium stream, all three cartridges performed at near 100% efficiency, as shown in FIGURE 4. With higher flow, direct-from-target delivery, the cartridges trapped [11C]CO2 with a wider range of efficiencies: ICOH (99 ± 1 %), ORTG (90 ± 2 %), and QMA (79 ± 4 %). Elution resulted in > 99 % release of carbon-11 activity for both QMA and ORTG cartridges, but only 39 ± 3 % release from the ICOH cartridge. Elution efficiency of the trapped radioactivity (Equation 5) was independent of the method of [11C]CO2 delivery. Across all cartridges and delivery methods, the eluate was at about pH = 10. We recommend that the ORTG cartridge be used for trapping of [11C]CO2 gas with elution by > 300 µL of saturated bicarbonate solution. This recommendation is based on the better trapping for ORTG cartridges compared to the QMA cartridges in the direct-from-target [11C]CO2 delivery method and the smaller volume needed for elution of all trapped carbon. This method excels based on its simplicity, adaptability to automation, low-cost ($5/cartridge), and observations that a single ORTG cartridge suffers no loss of performance after multiple uses. A potential disadvantage to this method is that it involves using a carbon-containing eluent, which means that this method cannot be used for imaging experiments that require high specific activity. However, considering the eluate is a mildly basic aqueous solution, we expect that it will be compatible with a wide variety of materials and experimental applications.

Klimatpåverkan från byggprocesser i Sverige uppgår till cirka 10 miljoner ton koldioxid årligen. Varav 40 procent beräknas komma från husprojekt och resterande 60 procent från anläggningsprojekt. I dagens samhälle finns ett stort intresse av att optimera byggnader till att bli så energisnåla som möjligt och därav så billiga som möjligt i drift. Vilket även medfört att miljöpåverkan från driftsektorn har minskat markant. Däremot betraktas sällan påverkan från framställning av ingående material och produktionen på bygget. En väl känd fras är att så mycket som 85 procent av en byggnads totala koldioxidutsläpp uppkom i drift och brukarskedet. Så är inte fallet i dagsläget, nu beräknas en byggnad under sin produktions- och bruksfas ha i princip samma miljöpåverkan genom koldioxidutsläpp. Materialval har under en längre tid gjorts efter vad de innehåller och hur det kommer påverka människans hälsa. Nu görs materialval även med tanke på mängd koldioxidutsläpp under dess livscykel. Vid val av material kan en avgörande skillnad för miljön och klimatets framtid göras. NCC folkboende är ett koncepthus av platsgjuten betong som är omtyckt av beställare och även av NCC att bygga. NCC bygger mycket bostäder och i många fall är det Folkboenden. Därför är det av intresse att undersöka hur ett byte av betongstomme till KL-trä påverkar byggnadens koldioxidutsläpp. Arbetet skall förtydliga om stombytet genererar en reducering av koldioxid samtidigt som det är möjligt att behålla det omtycka konceptets planlösningar. Det som framgår av examensarbetet är hur ett hus på åtta våningar påverkas av att stommen byggs i KL-trä jämfört med att platsgjutas. I miljödelen av arbetet behandlas framställning av de olika materialen samt dess transport till bygget. Dimensionering av byggnaden påvisar att samma planlösning i lägenheter är möjlig att behålla, samtidigt som en reducering på 20 procent gentemot ursprungliga stommens koldioxidutsläpp erhålls. Examensarbetet kan fungera som ett underlag för NCC att motivera trä som stommaterial till kund genom att påvisa den reducering av koldioxid som är tillgänglig för dem att bidraga med. / Climate influences from building processes in Sweden is around 10 million tonnes of carbon dioxide each year. In today’s society there is a big interest in to get buildings as energy effective as possible and thru that also less expensive to own. This has also caused that the impact on the environment have become a little smaller. In a while ago it was said that a building had 85 percent of its total carbon dioxide emissions during the operational phase. Now a day’s the impact of carbon dioxide during operational phase and impact of construction phase is pretty much the same. Materials have since a while back been chosen for what impact it has on the personal health. Today there’s also a lot of thought on what impact the material have on the environment thru carbon dioxide during its lifecycle. When choosing material an important difference for the future environment can be done. NCC Folkboende is a concept building that’s grout on site. The concept is popular among its clients and also among NCC to build. Since NCC are building a lot of housings and not rarely Folkboende its interesting to see what effect the change of framework has on carbon dioxide emissions and if it’s possible to keep the popular planning. This report will show how an eight stories high concrete building will be affected if the framework would be of cross-laminated timber instead of reinforced concrete. The building will be sized and proved to be able to keep the same planning on the housing, together with a 20 percent carbon dioxide reduction thanks to the material choice. This report could be used as basis for NCC to convince its clients to choose a framework of CLT without affecting the planning and at the same time make the environment a good favor.

Introduction Recently in our laboratory we needed a reliable and relatively simple source of aqueous solutions of [11C]CO2. We examined various methods of trapping [11C]CO2 gas both in solution and on ion exchange resins, followed by elution into aqueous phase. We favor simple methods that have high trapping and elution efficiencies and produce a highly concentrated solution. Furthermore, we desired methods that would minimize the use of hazardous reagents and materials with respect to both handling and disposal. We also considered the formulation of the final solution in terms of chemical compatibility with contacted materials, working with the assumption that dilute bicarbonate or carbonate solutions will have little reactivity with many materials. In a phantom, compatibility with materials (i.e. plastics, glues, metals, etc.) is important (1-4), while in (bio)geochemical studies – where transport of carbon is important – the chemical form of the radiolabelled molecule is important, but compatibility must be determined on a case-by-case basis (5-7). Small medical cyclotrons can easily produce carbon-11 as gaseous [11C]CO2, and various methods are utilized to incorporate carbon-11 into solution, often with unfavorable resource requirements, costs, or chemical properties. Commonly [11C]CO2 gas is bubbled through a strong base, forming the carbonate anion; but neutralizing a strong base (as to avoid special handling or disposal requirements) requires a large volume of diluent or buffer; or a very precise addition of acid – which if done improperly – may lead to an acidic pH and subsequent loss of [11C]CO2 from solution (8,9). Alternatively, [11C]CO2 (or [11C]CH4) can be converted to [11C]CH3I at high-yield, but requires specialized, expensive radio-synthesis equipment (10-12). [11C]CH3I can then be trapped in DMSO (albeit providing a volatile and hazardous solution) or used as a synthon en route to water soluble compounds such as [11C]choline (13). Finally, leftover radiolabelled radiopharmaceuticals from a carbon-11 imaging experiment could be used, but chemical compatibility (i.e. lipophilicity) of the radiolabelled compound may be of concern. Carbon dioxide gas will dissolve with a solubility of 1.5 g/L at STP (9) and slowly react with water to generate carbonic acid (H2CO3), a weak acid. Passing [11C]CO2 through a base-activated ion exchange cartridge, the [11C]CO2 reacts with hydroxide ions to form [11C]carbonate which is bound to the resin due to its higher selectivity for carbonate than hydroxide (14). Elution with excess bicarbonate displaces [11C]carbonate and neutralizes any remaining hydroxide, providing a 11C aqueous solution that is mildly basic, chemically non-hazardous, and very concentrated. Material and Methods [11C]CO2 gas trapping efficiency was evaluated for solutions and base-activated ion exchange resins. The gas was delivered either rapidly in a high-flow bolus directly from the cyclotron target or slowly in a low-flow helium stream during heating of a carbosieves column. Elution efficiency of ion exchange cartridges were evaluated for both fraction of trapped activity eluted and volume of solution needed for elution. [11C]CO2 was produced via the 14N(p,α)11C reaction on a CTI RDS111 – 11 MeV cyclotron at the Lawrence Berkeley National Laboratory’s Bio-medical Isotope Facility. The 7 mL target is pressurized to 315 psi with 1% O2/N2 gas, equating to 150 mL gas at STP. For direct-from-target trapping experiments, the target was decompressed and routed to the cartridge via 50 feet of 0.020” I.D. tubing until the target falls to atmospheric pressure (~55 seconds) providing an inhomogeneous flow – a short rapid burst of flow followed by a longer low-flow bleed. For helium-eluted experiments, the [11C]CO2 was unloaded from the cyclotron target and trapped on a room-temperature carbosieves column (15). Target gases were subsequently flushed from the column for 30 seconds with helium at 50 mL/min. After heating the column to 125 °C without gas flow, [11C]CO2 was eluted off the column in helium at 15 mL/min. [11C]CO2/He was bubbled through 9 aqueous and 2 organic solutions to test for trapping efficiency in a slow, steady helium stream at 15 mL/min (sodium hydroxide (0.96M, 0.096M, 0.0096M), sodium bicarbonate (1.14M, 0.57M, 0.057M), sodium carbonate (2.0M, 1.0M, 0.10M), ethanol, and DMSO (2mL ea.). An Ascarite-filled cartridge was attached to trap any untrapped [11C]CO2. Measures of radioactivity were made using a Capintec CRC-15R dose calibrator. Trapping efficiency for solutions is calculated as the fraction of radioactivity captured in solution relative to the sum of the solution and the Ascarite trap. Three different commercially available, ion ex-change cartridges were evaluated for trapping and elution efficiencies. FIGURE 1 shows a photo-graphic comparison of the physical size and shapes of the cartridges as well as a X-ray computed tomography (CT) cross sectional view of the internal ion exchange resin volume and dead volume of the cartridges. All cartridges were activated with 1 mL of 1 N aqueous NaOH followed by passing 10 mL deionized water then 10 mL of air through the cartridge. In both direct-from-target (n = 4) and helium-stream experiments (n = 3 or 4), cartridges were connected to [11C]CO2 delivery lines via Luer connections. The gas exiting the cartridge passed through an empty 3 mL crimp-top vial as a liquid trap en route to an Ascarite trap on the vent needle as described above. Trapping efficiency for cartridges is calculated as the fraction of radioactivity captured on the cartridge relative to the sum of the cartridge, the empty vial, and the Ascarite trap. Cartridges were eluted with 0.5 mL of saturated sodium bicarbonate solution (1.14 M @ 20°C) followed by 9.5 mL water and 10 mL air. Elution efficiency is calculated as the fraction of radioactivity eluted in 10 mL relative to the sum of the spent cartridge following elution and the 10 mL eluate (Equation 5). The pH of the eluate was measured using 0-14 pH test strips. Results and Conclusion The trapping of [11C]CO2 in all solutions was less than 70% of the total radioactivity with the exception of the 0.96 M and 0.096 M NaOH. With a higher concentration of base driving equilibrium towards carbonate stability, it could be expected that the most basic solution had the best trapping efficiency, but this attribute also means it is least desirable solution to work with from a hazardous material or chemical compatibility perspective. When [11C]CO2 was delivered in a helium stream, all three cartridges performed at near 100% efficiency, as shown in FIGURE 4. With higher flow, direct-from-target delivery, the cartridges trapped [11C]CO2 with a wider range of efficiencies: ICOH (99 ± 1 %), ORTG (90 ± 2 %), and QMA (79 ± 4 %). Elution resulted in > 99 % release of carbon-11 activity for both QMA and ORTG cartridges, but only 39 ± 3 % release from the ICOH cartridge. Elution efficiency of the trapped radioactivity (Equation 5) was independent of the method of [11C]CO2 delivery. Across all cartridges and delivery methods, the eluate was at about pH = 10. We recommend that the ORTG cartridge be used for trapping of [11C]CO2 gas with elution by > 300 µL of saturated bicarbonate solution. This recommendation is based on the better trapping for ORTG cartridges compared to the QMA cartridges in the direct-from-target [11C]CO2 delivery method and the smaller volume needed for elution of all trapped carbon. This method excels based on its simplicity, adaptability to automation, low-cost ($5/cartridge), and observations that a single ORTG cartridge suffers no loss of performance after multiple uses. A potential disadvantage to this method is that it involves using a carbon-containing eluent, which means that this method cannot be used for imaging experiments that require high specific activity. However, considering the eluate is a mildly basic aqueous solution, we expect that it will be compatible with a wide variety of materials and experimental applications.

This licentiate thesis examines environmental assessment tools for buildings. This is done by investigating, analysing, comparing and testing how different environmental assessment tools measure the environmental performance of buildings and examining the consequences this may have on architectural design. The study begins by analysing three environmental assessment tools: Leadership in Energy and Environmental Design (LEED), Code for Sustainable Homes (CSH) and EcoEffect. These tools are then tested on a case study building (an eight-storey residential building) to analyse differences regarding assessment results, improvement proposals and potential impacts on architectural design. One of the environmental impacts assessed in the three tools, namely Climate Change caused by gases having Global Warming Potential (GWP), is then analysed in greater detail from a life cycle perspective by measuring CO2-equivalents (CO2-eq). A basic calculation tool (referred to as the ENSLIC tool), based on life cycle assessment methodology, is used to assess a case study building (a four-storey office building in Gävle). The CO2-eq emissions from a building’s material production and energy use are calculated and the impacts of a number of suggested building improvements and changes of energy sources are analysed.  The studies show the complexity of assessment tools and different ways to make comparisons. Both similarities and differences between the tools are apparent, regarding hierarchical structure and also on each hierarchical level, from categories to issues and parameters. It is also shown that the choice of environmental assessment tool may have an influence on the architectural design of buildings. The difficulty with assessing complex buildings is apparent even when only one environmental issue is assessed with the LCA-based ENSLIC tool. Many aspects influence the assessment result. These include energy use, choice of materials and choice of energy sources. The complexity and difficulty in linking buildings to environmental impact create a need for interactive tools measuring environmental performance, which can be useful as decision support in the early design phase. / Denna licentiatavhandling behandlar miljöbedömningsmetoder för byggnader. Arbetet bygger på undersökningar analyser, jämförelser och tester av hur miljöbedömningsmetoder bedömer byggnaders miljöprestanda och undersöker även vilka konsekvenser som detta kan ha på arkitektonisk utformning. Forskningen börjar med att tre miljöbedömningsmetoder, Leadership in Energy and Environmental Design (LEED), Code for Sustainble Homes (CSH) och EcoEffect analyseras och jämförs. Sedan genomförs en fallstudie där de tre metoderna testas på ett bostadshus (ett åttavåningar högt bostadshus i Stockholm). Skillnader gällande miljöbedömningsresultat och miljöbedömningmetodernas förslag på förbättringsåtgärder samt eventuell påverkan på den arkitektoniska utformningen analyseras och diskuteras. En av miljöpåverkanskategorierna som bedöms i de tre metoderna, klimatpåverkan orsakad av gaser med inverkan på den globala uppvärmningen, analyseras sedan mer i detalj utifrån ett livscykelperspektiv genom att mäta byggnaders utsläpp av koldioxidekvivalenter (CO2 ekv). Ett förenklat beräkningsverktyg (som här benämns ENSLIC-verktyget), som är baserat på livscykelmetodik, används för att studera en byggnad (ett fyra våningar högt kontorshus i Gävle). Sedan beräknas utsläppet av CO2 ekv från byggnadens material- och energianvändning. Effekten av ett flertal föreslagna förbättringsåtgärder på byggnaden samt byte av energikällor analyseras också. Studierna visar på miljöbedömningmetodernas komplexitet och presenterar olika sätt att göra jämförelser på. Skillnader och likheter mellan metoderna påvisas gällande hierarkisk struktur och även på varje hierarkisk nivå, från kategorier till enskilda bedömda frågor och parametrar. Dessa skillnader talar för att olika metoder kan påverka den arkitektoniska utformningen av byggnader. Svårigheten i att bedöma komplexa byggnader belyses även när endast en miljöpåverkan bedöms med det livscykelanalys baserade ENSLIC-verktyget. Många saker påverkar resultatet, framförallt energianvändning tillsammans med materialanvändning och val av energikällor. Den komplexa och svåra uppgiften att länka samman byggnader med deras miljöpåverkan öppnar upp för användande av interaktiva verktyg som mäter miljöpåverkan som kan användas som beslutshjälpmedel i tidiga designskeden. / QC 20101123

The fluids that are operated above their critical temperature and pressure are known as supercritical fluids (SCFs). SCFs replaces the conventional organic solvents in the chemical processes due to their attractive properties such as liquid like densities, gas like diffusivities, negligible surface tension, lower viscosity and high compressibility. Carbon dioxide, being non-toxic, non-flammable with ambient critical temperature and moderate critical pressure, is the most widely used SCF in many chemical processes. Supercritical carbon dioxide (SCCO2) finds applications in industrial processes such as extraction and separation processes. The feasibility of a supercritical process can be determined from the solubility of solute in SCF. For the efficient design of a SCF process, the effects of temperature and pressure on the solubility of a solid should be examined thoroughly. In general, the solute of interest is not present alone; it is present along with many other components in the compound. The solute has to be extracted or separated from matrix of components. Therefore, it is important to determine the mixture solubilities in SCCO2. The mixture solubility of a solute is not same as that of pure component solubility. The presence of the other component alters the solubility of the solute to a greater extent; hence the effects of the other components present along with the solute, temperature and pressure need to be known to understand the mixture behavior of the solute in SCCO2. The solubilities of solid isomers (ortho-, meta-, para-) in SCCO2 vary to a greater extent. This huge difference in the solubilities of isomers is due to interactions between the molecules. The high solubility of an isomer in SCCO2 might be due to the solute-solvent interactions. The interactions between the molecules are significant in the solid mixtures solubilities in SCCO2. This research work focuses on experimental determination and modeling of mixture solubilities of solids in SCCO2. The solubilities of several pairs of isomers have been experimentally determined at different temperatures and pressures. These include the ternary solubilities of ntrophenols, nitrobenzoic acids and dihydroxy benzene isomers mixtures in SCCO2. The experimental solubilities of nitrophenol (meta- and para-) isomers mixture have been determined. This study includes the effect of temperature, pressure and each isomer on the ternary mixture solubilities of nitrophenol mixtures. The enhancements in the ternary solubilities of nitrophenols over their binary solubilities and the selectivity of SCCO2 for the nitrophenol mixture have been discussed in detail. The solubilities of dihydroxy benzene (ortho-: pyrocatechol, meta- : resorcinol and para-: hydroquinone) isomers in SCCO2 have been determined at various temperatures and pressures. The ternary solubilities of pyrocatechol and resorcinol and quaternary solubilities of pyrocatechol, resorcinol and hydroquinone mixtures in SCCO2 have been investigated. The effect of each isomer on the mixture solubilities of other isomers has been included in this work. Selectivity for dihydroxy benzene isomers and variation of solubilities enhancements with temperature and pressure has been presented in this study. The equilibrium mixture solubilities of nitrobenzoic acid isomers (meta- and para) mixture have been studied. The variation of mixture solubilities and their enhancements with temperature and pressure has been thoroughly analyzed. Selectivity of SCCO2 for this nitrobenzoic acid mixture has been studied in detail. The increase or decrease in the ternary solubilities of the solid mixtures that have been considered in this study is due to the interactions between the molecules. The ternary solubilities of m-nitrophenol increase whereas they decrease for pnitrophenol for the nitrophenol solid mixture. Quaternary solubilities of dihydroxy benzene isomers (pyrocatechol + resorcinol + hydroquinone) increases compared to their pure component solubilities. The ternary solubilities of pyrocatechol increases while resorcinol decreases over the pressure range at different temperatures (except 338 K) considered in this study. The mixture solubilities of p-nitrobenzoic acid of nitrobenzoic acid isomers increase to a greater extent. An average of separation efficiency of 70%, 85% and 90% has been observed for ternary solid mixtures of nitrophenol, nitrobenzoic acid and dihydroxy benzene isomers respectively. Modeling of high pressure multi-component systems is useful to understand the behavior of the mixtures. Moreover, the experimental determination of multicomponent solubilities of solids in SCCO2 is tedious and time consuming; hence the modeling of mixture solubilities is essential. The interactions between the molecules have been incorporated in the association theory and a five parameter equation with two constraints has been derived for binary systems. The new equation correlates the solubilities of m-dinitrobenzene in this study along with 72 other systems available in literature. Seven new model equations have been developed to correlate ternary (2 for cosolvent (solid + cosolvent + SCCO2) systems; 5 for solid mixtures in SCCO2) solubilities of solids in SCCO2. A new model equation for cosolvent ternary systems has been derived by using the concepts of association of molecules. The model equation contains seven adjustable parameters with three constraints and correlates mixture solubilities in terms of temperature, pressure, density and cosolvent composition. The interactions between the molecules have been included in the association theory then the number of parameters decreased to five with two constraints. The performance of the newly developed equations has been evaluated for 32 ternary systems with various cosolvents along with experimental data of mdinitrobenzene in methanol cosolvent of this study. The same association theory has been extended to ternary (solid mixtures + SCCO2) solubilities of solids in SCCO2 and two new equations have been derived with and without incorporating interactions between the molecules. Both the equations have five adjustable parameters with three constraints for the equation which has been derived from association theory alone and two constraints for the equation which has been derived by considering the interactions between the molecules in the association theory. A new model equation has been derived by combining solution model with Wilson activity coefficient model to account for nonidealities of the solute. This equation has four adjustable parameters and no constraints on the parameters. The non-idealities of both solutes in the solution model have been included and two more equations with no constraints on the parameters have been developed. One equation uses NRTL activity coefficient model which results in three adjustable parameters while the other equation with five parameters has been obtained from Wilson activity coefficient model for solid mixtures solubilities in SCCO2. The performance of the newly developed equations has been evaluated for the solid mixtures (ternary systems) in SCCO2. The equations with constraints make them limited for few systems and the equations with no constraints are able to correlate the solubilities of solids of all the ternary systems that are available in literature along with the generated ternary experimental data of this study. The quaternary solubilities of solids have been correlated by using a five parameter model equation which has been derived by combining solution and Wilson activity coefficient models. The equation for the quaternary systems does not have constraints on the parameters; hence can be applied for quaternary systems. The equation correlates the quaternary solubilities of solids in terms of temperature, pressure, density and cosolute compositions. Chapter 1 gives a brief introduction on the solubilities of solid mixtures and their behavior in SCCO2. Chapter 2 presents the experimental setup and the solubility data of binary, ternary and quaternary systems determined in this study. Chapter 3 focuses on the models that have been derived to correlate the solubilities of solids in SCCO2. Chapter 4 discusses in detail about the results obtained in this research work. Chapter 5 briefly summarizes the work and presents major conclusions. The new equations that have been developed here are first of its kind for the ternary and quaternary systems. These equations give information about the nonidealities of the systems. The nature of the interactions between the molecules can be determined from the parameters of the equations which incorporate interactions between the molecules. The multi-component solubilities of the solids can be correlated by using the semi-empirical equations that have been derived in this research.

Fossil fuel and advanced industrialization techniques contribute to global warming through emissions of greenhouse gases such as CO2. In order to mitigate climate change, there is a desperate need to reduce CO2 emissions from different sources. CO2 capture and sequestration (CCS) play an important role in these reductions. Naturally occurring enzymes, e.g., carbonic anhydrase (CA), can catalyze these reactions in living systems. Much effort has been focused on complexes of zinc with ligands such as teta, cyclen and tripodal ligands including BIMA and Trispyrazolylborates. These complexes have many interesting CO2 capture properties, but maintain toxic perchlorate ions. We desired to replace them with less hazardous counteranions like BF4- or PF6-. Our research focused mainly on the synthesis and characterization of Zn, Co and Cu cyclen and teta complexes that could mimic CA. We also examined some of these species for catalytic CO2 hydration behavior on wetted-wall column (WWC) at Center for Applied Energy Research (CAER). We successfully synthesized and characterized eight new complexes. These catalysts as CO2 capture systems are more stable have low molecular weights (compared to CA) and more cost effective than enzymes. In terms of catalytic activity significant results were obtained only for few of the catalysts

Introdução: As diversas armadilhas apresentam rendimento diferenciado na captura, havendo a necessidade de buscar instrumentos que amostrem porções representativas das populações de mosquitos. Levanta-se a hipótese de que as armadilhas Mosquito Magnet Independence e CDC com CO2+Lurex3 sejam mais eficazes na captura de culicídeos do que a armadilha CDC luminosa. Objetivos: Avaliar a eficácia das armadilhas Mosquito Magnet Independence e CDC+CO2+Lurex3, em relação à CDC-luminosa, para a captura de culicídeos adultos em área agrícola na Fazenda Experimental em Pariquera-Açu, Vale do Ribeira, São Paulo, Brasil. Material e Métodos: Capturas mensais, das 15h00 às 21h00, por meio do delineamento em quadrado latino 3X3, no período de dezembro/2010 a novembro/2011. Perfis de diversidade de Rényi e índices de riqueza, dominância, diversidade, equabilidade e similaridade foram estimados para cada armadilha para compará-las. Resultados: Capturou-se 6.055 de 70 espécies e 12 gêneros. A CDC-luminosa amostrou 990 indivíduos de 42 espécies e 10 gêneros,a CDC+CO2+lurex31.419 indivíduos em 41 espécies e 10 gêneros e a Mosquito Magnet 3151 indivíduos de 46 espécies e 11 gêneros. A riqueza, pelo índice de Margalef e Perfil de Rényi, não apresentou diferença estatística para nenhuma armadilha no período dez/mai. A Mosquito Magnet obteve maior rendimento na mensuração da diversidade, segundos os índices de Shannon e Simpson, observados no perfil de Rényi. A dominância, pelo índice de Berger-Parker isolado,foi maior na Mosquito Magnet do que nas demais, nos dois períodos de capturas. O perfil de Rényi não apontou diferença significante para dominância. Índice de Pielou não mostrou significância em relação à CDC-luminosa para nenhuma das armadilhas nos dois períodos avaliados. Índices de Jaccard e Sorensen apontaram maior similaridade na composição de espécies entre a Mosquito Magnet e CDC+CO2+lurex3. Conclusões: A Mosquito Magnet Independence e CDC+CO2+Lurex3 apresentaram rendimento semelhante, nos meses mais frios e secos do ano. A utilização dessas armadilhas para a captura de determinados táxons pode ser importante ponto na estratégia de vigilância de espécies vetoras. Estudos com maior esforço amostral devem ser realizados para avaliar o rendimento das armadilhas Mosquito Magnet Independence e CDC+CO2 +lurex3 em áreas de ambiente alterado de Floresta Atlântica. / Introduction: The several traps have different performance in sampling mosquitoes,with the need to seek that capture representative portions of mosquito population. Formulate the hypothesis that the Mosquito Magnet trap and CDC+CO2+lurex3 are more effective in catching mosquitoes than the CDC light trap. Objectives: To evaluate the effectiveness the Mosquito Magnet Independence and CDC+CO2+lurex3 in relation to CDC light trap, to catching adult mosquitoes in the agricultural area at the Experimental Station in Pariquera-Açu, Vale do Ribeira, São Paulo, Brazil. Methods: Monthly captures, from 03:00pm-09:00pm, through the 3X3 Latin square from the December 2010 to November 2011. Rényi diversity profiles and indexes of the richness, dominance, diversity, evenness and similarity were estimated for each trap to compare them. Results: Were captured 6055 mosquitoes of the 70 species and 12 genera. CDC light traps sampled 990 specimens of 42 species and 10 genera, the CDC+CO2+lurex3 sampled 1419 specimens in 41 species and 10 genera and 3151 specimens were captured in the Mosquito Magnet belonging to 46 species and 11 genera. The richness, by the Margalef index on profile Rényi, showed no statistical difference for any trap in the period Dez/Mai. The Mosquito Magnet trap obtained higher yield in the measurement of diversity, according indexes of Shannon and Simpson, seen in profile Rényi. The dominance, by Berger-Parker index isolated, was higher in the Mosquito Magnet than in the other traps in both periods of captures. The profile Rényi showed no significant difference for dominance. Pielou index was not significant in relation to CDC light trap for any of the periods. Jaccard and Sorensen indexes showed greater similarity in composition of species between the CDC+CO2+lurex3 and Mosquito Magnet. Conclusions: The Mosquito Magnet Independence and CDC+CO2+ Lurex3 showed similar performance in colder and drier months of the year. The use of these traps to capture certain taxa can be important point in the surveillance approach vector species. Studies with greater sampling effort should be made to evaluate the performance of the Mosquito Magnet Independence and CDC+CO +lurex3 traps changed environment in areas of Atlantic Forest.