In order to reduce the amount of pollution that is generated by burning fossil fuels alternative energy sources should be explored. Hydrogen has been identified as the most promising replacement for fossil fuels and can be produced by using the Hybrid Sulphur (HyS) cycle. Currently the SO2/O2 separation step in the HyS process has a large amount of knock out drums. The aim of this study was to investigate new technology to separate the SO2 and O2. The technology that was identified and investigated was to separate the SO2 and O2 by absorbing the SO2 into an ionic liquid. In this study the maximum absorption, absorption rate and desorption rate of SO2 from the ionic liquid [BMIm][MeSO4] with purities of 95% and 98% was investigated. These ionic liquid properties were investigated for pure O2 at pressures ranging from 1.5 to 9 bar(a) and for pure SO2 at pressures from 1.5 to 3 bar(a) at ambient temperature. Experiments were also carried out where the composition of the feed-stream to the ionic liquid was varied with compositions of 0, 25, 50, 75 and 100 mol% SO2 with O2 as the balance. For each of these compositions the temperature of the ionic liquid was changed from 30oC to 60oC, in increments of 10oC. The absorption rate of SO2 in the ionic liquid increased when the mole percentage SO2 in the feed stream was increased. When the temperature of the ionic liquid was decreased the maximum amount of SO2 that the ionic liquid absorbed increased dramatically. However, the absorption rate was not influenced by a change in the absorption temperature. The experimental results for the maximum SO2 absorption were modelled with the Langmuir absorption model. The model fitted the data well, with an average standard deviation of 17.07% over all the experiments. In order to determine if the absorption reaction was endothermic or exothermic the Clausius-Clapeyron equation was used to calculate the heat of desorption for the desorption step. The heat of desorption data indicated that the desorption of SO2 from this ionic liquid was an endothermic reaction because the heat of desorption values was positive. Therefore the absorption reaction was exothermic. From the pressure-change experiments the results showed that the mole percentage of O2 gas that was absorbed into the ionic liquid was independent of the pressure of the O2 feed.On the other hand, there was a clear correlation between the mole percentage SO2 that was absorbed into the ionic liquid and the feed pressure of the SO2. When the feed pressure of the SO2 was increased the amount of SO2 absorbed also increased, this trend was explained with Fick’s law. In the study the effect of the ionic liquid purity on the SO2 absorption capacity was investigated. The experimental results for the pressure experiments showed that the 95% and 98% pure ionic liquid absorbed about the same amount of SO2. During the temperature experiments the 95% pure ionic liquid absorbed more SO2 than the 98% pure ionic liquid for all but two of the experiments. However the 95% pure ionic liquid also absorbed small amounts of O2 at 30 and 40oC which indicated that the 95% pure ionic liquid had a lower selectivity than the 98% pure ionic liquid. Therefore, the 95% pure ionic liquid had better SO2 absorption capabilities than the 98% pure ionic liquid. These result showed that the 98% pure ionic liquid did not absorb more SO2 than the 95% pure ionic liquid, but it did, however, show that the 98% pure ionic liquid had a better selectivity towards the SO2. Hence, it can be concluded that even with the O2 that is absorbed it would be economically more advantageous to use the less expensive 95% pure ionic liquid rather than the expensive 98% pure ionic liquid, because the O2 would not influence the performance of the process negatively in such low quantities. / Thesis (MIng (Chemical Engineering))--North-West University, Potchefstroom Campus, 2013

Thematic interrelation is an underdeveloped field of inquiry in Lukan studies. The design and elegance of Lukan theology begs for guided investigation into a possible system of organisation that governs history and theology, that is, narrative and theme. Based on the Greimasian Actantial Model, morpho–syntactical structural–critical analysis of Luke and Acts reveals that the covenant concept in its operative aspect of service functions as an organising principle, structuring the narratives and facilitating thematic interrelation. A survey of representative Lukan research consisting of five methodologically determined approaches shows a commonality regarding Lukan purpose. These all share the “plan of God” as a fundamental concept, thus intimating its plausibility as a common organisational principle in the text. This observation encourages further analysis of Lukan narrative and meta–narrative as relevant subject matter. Investigation into the purpose and goals of Ancient Jewish and Ancient Greek literature suggests that the concepts of piety/holiness and justness combined with a notion of divine order and expectation demonstrates organisational capacity. Under the terms and conditions of the Old Covenant three non–exclusive themes/concepts hold organisational functionality and ability to facilitate thematic interrelation: Exodus typology, the covenant concept and the eschaton idea. Exodus typology connects narrative with theme, developing Israel’s story. The covenant idea frames stories using parallelism and gives the meta–story progression. The eschaton idea presents the Day of YHWH as an organisational principle guiding the story of judgment to restoration. It is observed that the covenant concept is the most prevalent of these themes/ideas. Assuming the conceptual unity of Luke and Acts and adopting a morpho–syntactical structuralist approach, it was observed that the covenant concept in its operative aspect of service occurred as Helper at ten places, determining the development and structure of the meta–narrative. According to the Greimasian Actantial Model, Israel failed to fulfil its covenant–based mandate to serve God and shine God’s light of mercy to the nations. Jesus, Israel’s new Helper, becomes the Subject and by his covenant–based ministry, characterised as the greatest service, resolves the problem that prevents Israel from carrying out its divine mandate and sets the stage for its fulfilment. In Jesus Israel is given new leaders, an ethical platform of discipleship and the Holy Spirit. The apostle Paul as the epitomised and exemplary witness and servant of Jesus fulfils what Israel could not. He is vindicated in righteousness and shares in the Isaianic ministry of Jesus, to bear witness to leaders and to shine God’s light to the nations. Paul is unhindered in this ministry. Additionally, in thematic–critical terms, the key placement of the covenant concept in its operative aspect of service at plot–defining junctures features its catalytic dynamic as a “template” concept advancing the re–conceptualising of themes and providing a platform for meaningful relation. The evidence thus suggests that the covenant concept in its operative aspect structures the conjoined narratives of Luke and Acts. It also provides a basis for relation between the divine and humans in the context of the history of God’s salvation, linking history and theology, and makes possible a discernible means to thematic interrelation. The SO2 electrolysis was performed by supplying the anode of the cell with SO2 gas, while the water was fed to the cathode using graphite plates as flow fields. Initial experimental work was done at ambient pressures on the anode (SO2 gas–fed) and cathode (water–fed) after which the water pressure was increased from ambient to 1 bar. Various parameters were evaluated for SO2 electrolysis at ambient conditions, including operating temperature, membrane thickness and catalyst loading. The operating temperature was increased from 50oC to 80oC which resulted in a significant voltage improvement from 0.78V to 0.64V at 300mA/cm2. Operating the cell with thinner membranes (86 vs 170um) also resulted in an improved overall cell performance, while the catalyst loading (1 vs 0.5mgPt/cm2) had a negligible effect on the operating voltage. SEM images and EDX analysis were performed on the best performing MEA (N1135) which showed that no degradation of the MEA had occurred. / Thesis (M.Sc. (Chemistry))--North-West University, Potchefstroom Campus, 2011.

Thematic interrelation is an underdeveloped field of inquiry in Lukan studies. The design and elegance of Lukan theology begs for guided investigation into a possible system of organisation that governs history and theology, that is, narrative and theme. Based on the Greimasian Actantial Model, morpho–syntactical structural–critical analysis of Luke and Acts reveals that the covenant concept in its operative aspect of service functions as an organising principle, structuring the narratives and facilitating thematic interrelation. A survey of representative Lukan research consisting of five methodologically determined approaches shows a commonality regarding Lukan purpose. These all share the “plan of God” as a fundamental concept, thus intimating its plausibility as a common organisational principle in the text. This observation encourages further analysis of Lukan narrative and meta–narrative as relevant subject matter. Investigation into the purpose and goals of Ancient Jewish and Ancient Greek literature suggests that the concepts of piety/holiness and justness combined with a notion of divine order and expectation demonstrates organisational capacity. Under the terms and conditions of the Old Covenant three non–exclusive themes/concepts hold organisational functionality and ability to facilitate thematic interrelation: Exodus typology, the covenant concept and the eschaton idea. Exodus typology connects narrative with theme, developing Israel’s story. The covenant idea frames stories using parallelism and gives the meta–story progression. The eschaton idea presents the Day of YHWH as an organisational principle guiding the story of judgment to restoration. It is observed that the covenant concept is the most prevalent of these themes/ideas. Assuming the conceptual unity of Luke and Acts and adopting a morpho–syntactical structuralist approach, it was observed that the covenant concept in its operative aspect of service occurred as Helper at ten places, determining the development and structure of the meta–narrative. According to the Greimasian Actantial Model, Israel failed to fulfil its covenant–based mandate to serve God and shine God’s light of mercy to the nations. Jesus, Israel’s new Helper, becomes the Subject and by his covenant–based ministry, characterised as the greatest service, resolves the problem that prevents Israel from carrying out its divine mandate and sets the stage for its fulfilment. In Jesus Israel is given new leaders, an ethical platform of discipleship and the Holy Spirit. The apostle Paul as the epitomised and exemplary witness and servant of Jesus fulfils what Israel could not. He is vindicated in righteousness and shares in the Isaianic ministry of Jesus, to bear witness to leaders and to shine God’s light to the nations. Paul is unhindered in this ministry. Additionally, in thematic–critical terms, the key placement of the covenant concept in its operative aspect of service at plot–defining junctures features its catalytic dynamic as a “template” concept advancing the re–conceptualising of themes and providing a platform for meaningful relation. The evidence thus suggests that the covenant concept in its operative aspect structures the conjoined narratives of Luke and Acts. It also provides a basis for relation between the divine and humans in the context of the history of God’s salvation, linking history and theology, and makes possible a discernible means to thematic interrelation. The SO2 electrolysis was performed by supplying the anode of the cell with SO2 gas, while the water was fed to the cathode using graphite plates as flow fields. Initial experimental work was done at ambient pressures on the anode (SO2 gas–fed) and cathode (water–fed) after which the water pressure was increased from ambient to 1 bar. Various parameters were evaluated for SO2 electrolysis at ambient conditions, including operating temperature, membrane thickness and catalyst loading. The operating temperature was increased from 50oC to 80oC which resulted in a significant voltage improvement from 0.78V to 0.64V at 300mA/cm2. Operating the cell with thinner membranes (86 vs 170um) also resulted in an improved overall cell performance, while the catalyst loading (1 vs 0.5mgPt/cm2) had a negligible effect on the operating voltage. SEM images and EDX analysis were performed on the best performing MEA (N1135) which showed that no degradation of the MEA had occurred. / Thesis (M.Sc. (Chemistry))--North-West University, Potchefstroom Campus, 2011.

No description available.

Les QTL (Quantitative Trait Loci) sont des régions chromosomiques comportant un ou plusieurs gènes contrôlant l’expression d’un paramètre péhnotypique. La détection de ces QTL dans l’industrie des levures œnologiques permet la sélection de souches performantes. Dans cette étude, la dissection d’un QTL associé à la phase de latence durant la fermentation alcoolique en conditions œnologiques a permis de mettre en évidence une nouvelle translocation. Celle-ci, impliquant le gène SSU1 permet aux souches qui la possèdent d’avoir une phase de latence raccourcie. L’usage intensif du SO2 en œnologie a conduit à la sélection de cette translocation chez les souhes industrielles. Des marqueurs PCR ont été developpés pour contrôler ce caractère dans les processus de sélection des souches, permettant d’intoduire cette translocation dans différents fonds génétiques. Une première étape dans l’étude de l’impact organoleptique de ces translocations sur le vin a été faite, montrant une corrélation avec la production d’acidité volatile. Cette voie reste néanmoins à approfondir, tant au laboratoire qu’en conditions réelles dans un chai. / QTL (Quantitative Trait Loci) are chromosomics regions including one or more genes controlling the expression of a phenotypic parameter. The detection of these QTL in the wine industry allows the selection of more efficient yeast strains. In this study, the dissection of a QTL linked to lag phase variation during wine alcoholic fermentation was carried out. Our findings put in light a new translocation involving the SSU1 gene conferring a shorter lag phase. The intensive use of SO2 in oenology allows the selection of this translocation in industrials strains. Genetic markers were developed for introducing this translocation in various genetic backgrounds during selection programs. The study of translocations impact on the wine organoleptic properties was initiated, showing an unexplained role of VIII-XVI translocation on the volatile acidity production. These preliminary results need to be continued, in laboratory and cellar conditions.

The problems of rape seed methyl ester (RME) production process by-products utilization were analyzed, statistical data for the capacities of biodiesel production and by-products generation were presented, the prospects of biodiesel production expansion, properties and environmental impact, main production technologies, Lithuanian and foreign countries experience were described, the main aims and tasks of work were defined. The investigation of glycerol – major by-product of RME production process – utilization was accomplished. One of the new possible utilization methods was researched, when combusting glycerol with highly sulphurous (~ 2.0 %) heavy fuel oil to reduce SO2 emissions, which limit value in the flue gas can not exceed 1700 mg/Nm3 (according to EU Directive 1999/32EC and LAND 43-2001 „Norms for the exhaust of pollutants from large fuel burning equipment“). The heavy fuel oil – glycerol emulsion was prepared in the pilot plant operating in the laboratory conditions, the most optimal ratio (1:1) for heavy fuel oil emulsification was estimated, the dispersivity investigation of heavy fuel oil - glycerol emulsion samples was performed. The experimental heavy fuel oil and obtained emulsion combustion investigations were carried out in VGTU Institute of Thermal Insulation pilot plant and in the thermal oxidation boiler „UMISA-CR/11,9 (13)“ at JCS „Rietavo veterinarinė sanitarija“. The CO, NOx, SO2 and particulate matter concentration values for heavy fuel oil and... [to full text] / Baigiamajame darbe išnagrinėtos rapso aliejaus metilo esterio (RME) gamybos proceso šalutinių produktų utilizacijos problemos, pateikti statistiniai duomenys apie biodyzelino gamybos bei susidarančių šalutinių produktų apimtis, aprašytos biodyzelino gamybos plėtros perspektyvos, savybės bei poveikis aplinkai, pagrindinės gamybos technologijos, Lietuvos bei užsienio šalių patirtis šioje srityje, apibrėžti pagrindiniai darbo tikslai ir uždaviniai. Atliktas RME gamybos proceso pagrindinio šalutinio produkto – glicerolio – utilizacijos tyrimas. Išanalizuotas vienas iš naujų galimų utilizavimo būdų - deginti glicerolį kartu su sieringu (~ 2,0 %) mazutu, siekiant sumažinti SO2 emisijas, kurių nustatyta ribinė vertė dūmuose negali būti didesnė kaip 1700 mg/Nm3 (pagal ES Direktyvą 1999/32EC ir LAND 43-2001 „Išmetamų teršalų ir didelių kurą deginančių įrenginių normos“). Laboratorinėmis sąlygomis stendiniame įrenginyje paruošta mazuto-glicerolio emulsija, nustatytas optimaliausias mazuto emulgavimo gliceroliu santykis (1:1), atlikti mazuto emulsijos bandinių homogeniškumo tyrimai. Eksperimentiniai mazuto bei gautų emulsijų deginimo bandymai buvo atlikti VGTU Termoizoliacijos instituto eksperimentiniame stende bei UAB „Rietavo veterinarinė sanitarija“ termooksidaciniame katile „UMISA-CR/11,9 (13)“. Išmatuotos mazuto ir mazuto-glicerolio emulsijos CO, NOx, SO2 ir kietųjų dalelių emisijos bei palygintos su jų didžiausiomis leistinoms vertėmis. Remiantis gautais rezultatais pateiktos... [toliau žr. visą tekstą]

Acidification of precipitation is an important environmental problem that emerged during the past century, especially after the Second World War. Acidification was primarily caused by human-made emissions of SOx (mostly SO2) and NOx, which are oxidized sulfur and nitrogen gases. The main sources of anthropogenic SOx emissions are non-ferrous ore refining, and the burning of fossil fuels and biofuels. SO2 emitted to the atmosphere combines with water vapor to produce sulfuric acid, which is one of the main compounds responsible for acid precipitation. In the 1970s and 1980s, more strict regulations regarding emissions of air pollutants such as SOx were established in Western Europe and North America, which led to declining levels of SO2 emissions and by this, declining levels of acidification in surface waters. This project was preformed by assembling and analyzing existing, publicly- available datasets of anthropogenic SO2 emissions for the period 1970 to 2010 from ten different regions in the Northern Hemisphere, and compare them with SO42- concentrations in precipitation and river chemistry in Sweden and Norway for the same period. It was discovered that it is the SO2 emissions from Northwestern Europe, the UK & Ireland and from the USA that have the greatest influence over the SO42- concentration in Scandinavian rivers. The SO42- concentration in stream water is also declining faster than the concentration in precipitation, with a faster decline in the southern parts of Scandinavia. / Försurning av nederbörd är ett miljöproblem som uppstod under det senaste århundradet, särskilt efter andra världskriget. Försurningen orsakades främst av mänskliga utsläpp av SOx (mestadels SO2) och NOx, vilka är oxiderade svavel- och kvävgaser. Huvudkällorna för dessa antropogena SOx-utsläpp är malmförädling samt förbränning av fossila bränslen och biobränslen. SO2 som släpps ut i atmosfären reagerar med vattenånga och bildar svavelsyra, vilket är en av huvudföreningarna ansvarig för sur nederbörd. På 1970- och 1980-talet fastställdes strängare bestämmelser beträffande utsläpp av luftföroreningar (som SOx) i Västra Europa och i Nordamerika. Detta ledde till minskande nivåer av SO2-utsläpp och genom denna sänkning även en minskning av försurning av ytvatten. Det här arbetet utfördes genom att befintlig, offentligt tillgänglig data samlades in och analyserades. Antropogena SO2-utsläpp för perioden 1970-2010 från tio olika regioner på norra halvklotet jämfördes med koncentrationer av SO42- i nederbörd och i vattendrag i Sverige och Norge för samma period. Genom detta fastslogs att de regioner som har störst inflytande över koncentrationen i skandinaviska vattendrag är SO2-utsläpp från nordvästra Europa, Storbritannien och Irland samt från USA. SO42- koncentrationen i vattendragen sjunker också snabbare än koncentrationen i nederbörden, med en snabbare nedgång i de södra delarna av Skandinavien.

In recent years an emphasis has been placed on the development of alternative and clean energy sources to reduce the global use of fossil fuels. One of these alternatives entails the use of H2 as an energy carrier, which can be obtained amongst others using thermochemical processes, for example the hybrid sulphur process (HyS). The HyS process is based on the thermal decomposition of sulphuric acid into water, sulphur dioxide and oxygen. The subsequent chemical conversion of the sulphur dioxide saturated water back to sulphuric acid and hydrogen is achieved in an electrolyser using a platinum coated proton exchange membrane. This depolarised electrolysis requires a theoretical voltage of only 0.158 V compared to water electrolysis requiring approximately 1.23 V. One of the steps in the development of this technology at the North-West University, entailed the establishment of the platinum coating technology which entailed two steps; firstly using newly obtained equipment to manufacture the membrane electro catalyst assemblies (MEA’s) and gas diffusion electrodes (GDE’s) and secondly to test these MEA’s and GDE’s using sulphur dioxide depolarized electrolysis by comparing the manufactured MEA’s and GDE’s to commercially available MEA’s and GDE’s. Different MEA’s and GDE’s were manufactured using both a screen printing (for the microporous layer deposition) and a spraying technique. The catalyst loadings were varied as well as the type and thickness of the proton exchange membranes used. The proton exchange membranes that were included in this study were Nafion 117®, sPSU-PBIOO and SfS-PBIOO membranes whereas the gas diffusion layer consisted of carbon paper with varying thicknesses (EC-TP01-030 – 0.11 mm and EC-TP01-060 – 0.19mm). MEA and GDE were prepared by first preparing an ink that was used both for MEA and GDE spraying. The MEA’s were prepared by spraying various catalyst coatings onto the proton exchange membranes containing 0.3, 0.6 and 0.9 mg/cm2 platinum respectively. The GDE’s were first coated by a micro porous carbon layer using the screen printing technique in order to attain a suitable surface for catalyst deposition. Using the spraying technique GDE’s containing 0.3, 0.6, 0.9 mg/cm2 platinum were prepared. After SEM analysis, the MEA’s and GDE’s performance was measured using SO2 depolarized electrolysis. From the electrolysis experiments, the voltage vs. current density generated during operation, the hydrogen production, the sulphuric acid generation and the hydrogen production efficiency was obtained. From the results it became clear that while the catalyst loading had little effect on performance there were a number of factors that did have a significant influence. These included the type of proton exchange membrane, the membrane thickness and whether the catalyst coating was applied to the proton exchange membrane (MEA) or to the gas diffusion layer (GDE). During SO2 depolarized electrolysis VI curves were generated which gave an indication of the performance of the GDE’s and MEA’s. The best preforming GDE was GDE-3 (0.46V @ 320 mA/cm2), which included a GDE EC-TP01-060, while the best preforming MEA’s were NAF-4 (0.69V @ 320mA/cm2) consisting of a Nafion117 based MEA and PBI-1 (0.43V @ 320mA/cm2) made from a sPSU-PBIOO blended membrane. During hydrogen production it became clear that the GDE’s produced the most hydrogen (best was GDE-02 a in house manufactured GDE yielding 67.3 mL/min @ 0.8V), followed by the Nafion® MEA’s (best was NAF-4 a commercial MEA yielding 57.61 mL/min @ 0.74V) and the PBI based MEA’s. , (best was PBI-2 with 67.11 mL/min @ 0.88V). Due to the small amounts of acid produced and the SO2 crossover, a significant error margin was observed when measuring the amount of sulphuric acid produced. Nonetheless, a direct correlation could still be seen between the acid and the hydrogen production as had been expected from literature. The highest sulphuric acid concentrations produced using the tested GDE’s and MEA’s from this study were the in-house manufactured GDE-01 (3.572mol/L @ 0.8V), the commercial NAF-4 (4.456mol/L @ 0.64V) and the in-house manufactured PBI-2 (3.344mol/L @ 0.8V). The overall efficiency of the GDE’s were similar, ranging from less than 10% at low voltages (± 0.6V) increasing to approximately 60% at ± 0.8V. For the MEA’s larger variation was observed with NAF-4 reaching efficiencies of nearly 80% at 0.7V. In terms of consistency of performance it was shown that the Nafion MEA’s preformed most consistently followed by the GDE’s and lastly the PBI based MEA’s which for the PBI based membranes can probably be ascribed to the significant difference in thickness of the thin PBI vs. the Nafion based membranes. In summary the study has shown the results between the commercially obtained and the in-house manufactured GDE’s and MEA’s were comparable confirming the suitability of the coating techniques evaluated in this study. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014

The ever increasing demand for a clean and renewable energy source has stimulated research for alternatives for the use of fossil fuels, which contribute significantly to global warming. The SO2 oxidation reaction was studied for production of hydrogen as a clean and renewable energy carrier. This reaction occurs at a lower standard electrode potential (0.158 V vs. SHE) than normal water electrolysis (1.23 V vs. SHE). This is a theoretical indication that the SO2 oxidation reaction has possible potential when compared to normal water electrolysis, since hydrogen production may occur at lower potentials and therefore lower cost. Rh was compared with Pt for the SO2 oxidation reaction since little research has been done on this catalyst and many studies exist in which Pt was used as catalyst. The oxygen reduction reaction and ethanol oxidation reaction were also included in this study to create a foundation for the catalysts studied, since the SO2 oxidation reaction is complicated by different adsorbed species that can form according to various mechanisms. The electrochemical techniques employed in this study to characterize the catalysts included cyclic voltammetry from which onset potentials and limiting current densities were determined, as well as from which some qualitative analysis was done. Linear polarization experiments were used during rotating disk electrode studies from which Levich and Koutecky-Levich analyses were done and the number of electrons transferred calculated and compared between the two catalysts. From the Koutecky-Levich analysis the kinetic current density was also obtained for use in Tafel analysis for further comparison between catalysts. It was found that Rh showed good behaviour for the oxygen reduction reaction when compared to Pt with similar onset potentials and limiting current densities. From Levich analysis it was concluded that both catalysts achieved diffusion limitation at high overpotentials. However, from the calculated number of electrons transferred it was evident that a difference in mechanism existed between catalysts and that the mechanism for both changed in the potential range studied, which is confirmed by the Tafel slopes. For the ethanol oxidation reaction it was shown that Rh exhibited very low catalytic activity in comparison with Pt. However, it was concluded from cyclic voltammetry and rotating disk electrode studies that more adsorbed species were present on the surface of Rh than on Pt. These results confirmed the possibility of using Rh as a co-catalyst together with Pt since it was shown from rotating disk electrode studies that low adsorption of ethanol and its oxidation products caused species to be transported away from the surface of the electrode during rotation. For the SO2 oxidation reaction it was found that Rh exhibited very poor catalytic activity together with being very susceptible to poisoning by adsorbed species. Pt showed very good behaviour, which corresponded well with what had been observed in literature. Levich analysis revealed that Pt did not exhibit diffusion limitation and Koutecky-Levich analysis revealed that a 2 electron reaction occurred on Pt, which corresponds with the SO2 oxidation reaction during which 2 electrons are transferred. It was, therefore, shown that Rh could exhibit good behaviour and act as a suitable catalyst in certain circumstances. However, for the SO2 oxidation reaction, which was the main focus of this study it was shown that Rh is not a suitable catalyst, either alone or as co-catalyst. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014

Master of Arts / Department of Economics / Tracy M. Turner / The report examines the extent to which the United States market for tradable pollution permits has been an efficient way to reduce sulfur dioxide emissions from coal-burning power plants. To do so, this report first provides background information on the effects of SO2 emissions on the environment in the United States. It discusses the initial attempt with the 1970 Clean Air Act to reduce these emissions and its degree of success. The details of the 1990 Amendments are then given. The economic theory behind the different methods of pollution control (quantity regulation, technology mandate, taxation, and emissions restriction through tradable permits) is explained and their efficiency regarding consumer and producer surplus is contrasted. The report then reviews published articles regarding the topic at hand. The U.S. Acid Rain Program has been found to be very efficient in its ability to reduce sulfur dioxide emissions at a low cost to the producers.