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Metallutvinning med fokus på zinkfrån avfallsflygaska med hjälp avsura processvatten / Metal mining focusing on zinc from waste fly ash by means of acidic process waterAbed, Samah, Al-Kaisee, Farah January 2016 (has links)
Syftet med projektet är att behandla flygaskan med hjälp av surt processvatten för att utvinna olika metaller, som zink, så att det sedan kan deponeras på ett enklare och billigare sätt, samt även at utveckla en metod för att utvinna mer zink med minsta möjliga andel surt processvatten (5 % HCl). Olika metaller med fokus på zink studerades i labbskala på Högskolan i Borås. Flygaskan och det sura processvattnet som har använts i denna studie är från Renova ABs anläggning. Resultatet visar att vid behandling av flygaskan med surt processvatten var den maximala mängden zink som utvanns 88% under de olika försöken som gjordes i labbet. Det finns olika faktorer bakom resultatet, såsom halten av surt processvatten, pH, blandningstiden och askans elementsammansättning, vilka kan påverka halten utvunnen zink. / Sweden produces large amount of fly ash from waste combustion annually. Combustion the waste generates two types of ashes, bottom ash/slag, and fly ash. Bottom ash is considered to be more environmentally friendly and has a wide area of application such as road constructions on landfills. While the fly ash has high level of heavy metals and for instance dioxines which are harmful for the environment. This type of ash are deposited in a landfill and gets classified as a hazardous waste which is expensive given that the deposit fee is high. The fact that fly ash contains valuable metals as zinc, methods of recovering it are being developed such as acid leaching. This is a promising method as the leachate used are acid process water making the usage of the chemicals substantially lower which makes it financially viable. Waste incinerators in Sweden produce approximately 200 000 tons of fly ash annually and the majority of it is transfered to Norway to get treated and put on a landfill. Some waste management companies, e.g. Renova, are using another method called “the Bamberg method” where fly ash is mixed with sludge to form a cake and put in the company’s own landfill. The projects goal is to leach the fly ash by using acidic process water to obtain the metallic substance particularly zinc making it easier and cheaper to landfill the ash and also to optimize this method to get the most zinc out of the ash using minimum amount of the acidic process water (5% HCI). The laboratory work took place in the University of Borås. Fly ash and the acid process water which were used under the laboratory work was obtained from RenovaAB. The results shows that leaching the fly ash with acidic process water gave different release of zinc but was 88% at most. The variation in the results depends on a few factors such as amount of acidic process water, pH, time, blending time and the ashes content. This project took environment and access to acidic water in consideration, which optimized the method of using less amount of acid process water to get the most zinc as possible. The results shows that leaching fly ash with acid process water is cost efficient and easy way to recover zinc, which satisfy the goals of the project.
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A method development for measuring lithium uptake inCaco-2 cells in a complex matrix using MP-AES – Appliedto evaluate the impact of humic acids on lithium uptakeHjelm, Erica January 2019 (has links)
Lithium, together with hydrogen and helium, were the only elements formed duringthe big bang. Lithium today, is a component in various products, some examples aregrease, ceramics, lithium-ion batteries and medication for bipolar disorder. Eventhough the knowledge of lithium’s interactions with biota and our environment islimited, the use of lithium is increasing. In humans, lithium is primarily absorbed in thesmall intestine through Na-channels. The average daily intake varies a lot, but in1985 it was estimated to range from 650 to 3100 μg for a 70 kg adult, according tointernational studies. However, it is not considered as a micronutrient and does nothave a recommended daily intake. Levels in some drinking waters are estimated toreach 170 μg L-1but no definite limit values are set. Humic substances are omnipresent in soil and freshwaters and is well known to formcomplexes with various cations such as most metals. In plants, the complexation ofcadmium and zinc with humic substances decreases their toxicity. However,currently, no studies have been published regarding if this is valid for animal cells aswell. To investigate if this is the case, in vitro tests were performed on Caco-2 cells,which originate from a colon carcinoma. These cells were exposed to a lithium concentration of 10 μg L-1in a nutrient medium for 2 hours. To a series of thesamples, humic acid was added to give a final concentration of 9.86 μg L-1 in thesolution to investigate if that would influence the lithium uptake. The study also includes a methodological evaluation if the performance of microplasma atomic emission spectroscopy (MP-AES) is suitable for the analyses of heavymatrices, e.g. nutrient medium and 1% Triton X solution. After optimization of instrumental parameters, it was concluded that MP-AES can beused for analysis of heavy and complex matrices. It requires, however, the use ofmatrix matched calibration solutions and addition of caesium as ionization buffer incombination with lithium signal correction using internal standards. It is alsoconcluded that lithium is absorbed by Caco-2 cells and that there was no indicationthat humic acid altered this uptake. / Litium är en viktig komponent in många produkter, bland annat smörjmedel, keramik,litium-jonbatterier och medicin mot bipolär sjukdom. Även fast dagens kunskap omlitium och dess interaktioner med miljö och organismer är begränsad, ökaranvändandet av litium. I människor absorberas litium primärt i tunntarmen genomNa-kanaler. Det dagliga intaget av litium varierar geografiskt och med livsstil och detfinnas inga bestämda gränsvärden. I USA var det dagliga intaget av litium 1985uppskattat att ligga kring 650 till 3100 μg hos en vuxen som väger 70 kg. Humusämnen är väl kända för att bilda komplex med flertalet metaller. I växter hardet påvisats att humusämnen kan bilda komplex med kadmium och zink vilketminskar toxiciteten av dessa för växten. Inga studier har dock hittats gällandehumusämnens eventuella möjligheter att minska toxiciteten av litium, eller andrametaller, hos djur eller människor. För att undersöka detta närmare har denna studiegjorts för att få ökad förståelse kring absorptionen av litium till Caco-2 celler samt föratt se om närvaro av humussyra kan påverka ett eventuellt upptag. Vidare presenteras resultat från en metodologisk utvärdering om MP-AES kananvändas för att kvantifiera litium i tyngre matriser, såsom näringsmedium för celleroch Triton X-100. Resultaten visar att MP-AES kan användas för dessa matriser genom att användamatrismatchade kalibreringslösningar och cesium som jonisationshämmare ikombination med korrigering av litiumsignalen med hjälp av signalen från internstandard. Sammanfattningsvis så absorberar Caco-2 celler litium och ingenindikation på att humusämnen påverkar detta upptag kunde hittas.
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Validation of MP-AES at the Quantification of Trace Metals in Heavy Matrices with Comparison of Performance to ICP-MSBerg, Isabelle January 2015 (has links)
The MP-AES 4200 using microwave plasma and an atomic emission spectroscopy detector provide a new and improved instrument to the analytical field. In this project will the performance of the equipment be evaluated in controlled NaCl-heavy matrices for selected metals (Cu, Zn, Li) and the result from this will be used to optimize a method for specific samples. These samples consist of combustion ashes from the incineration of hazardous waste and are provided by the company SAKAB AB. The sample preparation consisted of several cycles of L/S 10 followed by microwave assisted dissolution with concentrated HNO3, aqua regia or 18.2 MΩ. An extended amount of metals were quantified for these samples (Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Li, Mn, Na, Ni, Pb, V, Zn) and most (not Ca, Li, K or Na) were compared with an ICP-MS instrument equipped with a collision cell used for the elements As, Fe and V. A final experiment was made on an L/S 10 of the samples to attempt to separate the metals from the salt with ion exchange, something that would make it possible to recycle this otherwise unused waste. The detection limits were all in the low μg L-1 except for Cd, Mn and Zn, which were between 2-4 μg L-1. The MP-AES was found to be able to handle matrices up to 5 g L-1 NaCl without a significant loss of response and provided near identical results to the ICP-MS for the elements that could be compared, this did not included the elements not quantified with the ICP-MS or V which was the only element under the limit of detection for the MP-AES. The experiment where an attempt was made to separate the metals from the salt was proven successful after treatment of bark compost and another type of waste ash as cation exchangers.
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Investigation of the Metal Content in Cress Seedlings fed with increased Concentration of Lead & Iron SolutionsBurton, Nikita January 2020 (has links)
Metals are essential nutrients for plant health, but not all metals are necessary and can sometimes be harmful towards plants depending on factors such as species, elemental composition in the soil and concentration of a metal. Iron (Fe), which is one of the most abundant metals in the earth’s crust is also one the most important nutrients for plant growth, as it is responsible for metabolism. Lead (Pb) has been widely outspoken to be a harmful pollutant to plants and has been shown in studies to have an impact on a plant’s physiology and morphology. The aim of this study is to analyze whether Pb and Fe influence the metal content of Garden cress (Lepidium sativum). A solution of Pb with the following concentrations; 2.4 g/L, 1.2 g/L, 0.48 g/L, 0.24 g/L, 0.12 g/L, 0.048 g/L and 0.024 g/L were used. Another solution of Fe with the following concentrations; 0.56 g/L, 0.28 g/L, 0.11 g/L, 0.056 g/L, 0.028 g/L, 0.011 g/L and 0.0056 g/L were also used. Then a combined solution of both Pb- and Fe solution were mixed with a volume ratio of 1:1 corresponding to the following concentrations of lead and iron, respectively; 0.024/0.0056 g/L, 0.048/0.0112 g/L, 0.12/0.028 g/L, 0.24/0.056 g/L, 0.48/0.112 g/L, 1.2/0.28 g/L were used. A total of 29 different metal contents were analyzed, which include; Aluminum (Al), silver (Ag), Barium (Ba), Beryllium (Be), Bismuth (Bi), Cadmium (Cd), Cobalt (Co), Copper (Cu), Fe, gallium (Ga), potassium (K), lithium (Li), magnesium (Mg), manganese (Mn), Molybdenum (Mo), sodium (Na), nickel (Ni), Pb, rubidium (Rb), selenium (Se), strontium (Sr), tellurium (Te), thallium (Tl), uranium (U), vanadium (V), zinc (Zn). Before initial analysis, microwave plasma atomic emission spectrometry (MP-AES) was applied with a test sample to evaluate if the acidified digestion method used with nitric acid and hydrogen peroxide was successful enough to be used for the original experiment. It was successful, so the cress samples underwent the same digestion method and were analyzed with inductive coupled plasma mass spectrometry (ICP-MS). The results showed that Pb overall decreased most metal contents, while Fe seemed to generally maintain a constant metal content of most metals. Fe fed cress seemed to grow the healthiest in appearance compared to Pb fed cress which grew the worst. Mixed solution Pb and Fe cress fed grew worse than Fe fed cress, but better than Pb fed cress. The growth quality was the worst with Pb fed and the best for controlled water fed cress. For mixed Pb and Fe solution fed cress the plants seemed to share similar qualities of both Pb- and Fe solution fed cress, with better growth capabilities than Pb fed cress, but worse than Fe fed cress. The high dilution factor during the sample preparation led to the fact that some trace and ultra-trace elements could not be determined, since their contents were below LOD or LOQ. Adapting the sample preparation procedure to these low concentrations would be a further improvement.
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Removal of hexavalent chromium in wastewater using granular ferric hydroxidesLovell, Jessica, Levin, Sandra January 2015 (has links)
This study took place in Malawi, south eastern Africa. Metal contamination of water and soil is a threat to the environment and human health and is a serious concern in many countries including Malawi. Blantyre is the city of commerce where most of the industry is located along the banks of the main rivers. Some of the industries produce wastewater, which due to poor access to wastewater treatment plants, is discharged without treatment into the environment. A match factory in Blantyre uses chromium as a colouring agent for match heads and very high concentrations of chromium(VI) have been measured downstream the factory with concentrations up to 56 mg/l, which is much higher than the WHO guidelines of 0.05 mg/l. Chromium(VI) mainly occurs as chromate CrO42- and dichromate Cr2O72- ions. They are both toxic and carcinogenic and can cause mutations and chromosomal aberrations. The aim of the study was to evaluate the efficiency of Granular Ferric Hydroxide (GFH) in adsorbing and removing chromium from an aqueous phase. Wastewater was collected from the match factory and by optimizing relevant parameters the removal efficiency was maximized. The parameters optimized were pH, dosage and contact time and the effect of initial concentration. After respective experiment, all samples were analysed for chromium using microwave plasma atomic emission spectroscopy (MP-AES). The optimum pH was chosen to 8.0, the dosage to 17.4 g GFH/l and the contact time to 2 hours for a 95% removal of total chromium in undiluted wastewater. The removal efficiency of the GFH was 2.84 mg Cr/g GFH. To implement wastewater purification with GFH a number of practical issues have to be taken into consideration. Above all, a sufficient stirring method has to be devised as the removal efficiency is much affected by improper stirring. / Denna studie genomfördes i Malawi, sydöstra Afrika. Metallföroreningar i vatten och mark är ett stort problem i många länder, inklusive Malawi. Landets centrum för industri och handel ligger i Blantyre där de flesta av industrierna ligger längs med floderna. En del industrier genererar utsläppsvatten och på grund av dålig tillgång till vattenreningsteknik och vattenreningsanläggningar släpps mycket av det förorenade vattnet obehandlat ut i naturen. En tändsticksfabrik i Blantyre använder kromsalter för att färga tändstickshuvudena röda och höga koncentrationer av sexvärt krom har uppmätts nedströms fabriken. De uppmätta koncentrationerna var upp till 56 mg/l vilket är betydligt högre än WHO:s riktvärde på 0,05 mg/l. Sexvärt krom förekommer som kromat CrO42- och dikromat Cr2O72- joner vilka båda är mycket toxiska och cancerframkallande och därmed ett hot mot miljö och människor. Syftet med studien var att undersöka om granulära järnoxider (GFH) kunde användas som en adsorbent för att rena utsläppsvatten från kromater. Utsläppsvatten hämtades från tändsticksfabriken och genom att optimera relevanta parametrar kunde GFHns adsorbtionseffektivitet maximeras. Parametrarna som optimerades var pH, dos, kontakttid och initialkoncentration. Efter respektive experiment mättes kromkoncentrationen med mikrovågsplasma atomemissionsspektroskopi (MP-AES) Det optimala pH-värdet valdes till 8.0, dosen till 17.4 g GFH/l med en kontakttid på 2 timmar för en 95.3% reningsgrad på outspätt utsläppsvatten. Adsorptionseffektiviteten på GFHn var 2.84 mg Cr/g GFH. För att implementera vattenrening med GFH behöver flera praktiska aspekter tas med i beaktning. Framförallt är det viktigt med en bra omrörning för att GFHn ska kunna adsorbera effektivt.
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Analyzing components of barrier coatings in different fractions during a repulping process.Särnholm, Evelina January 2021 (has links)
During paper manufacturing, coating and adhesives are added to paper and cardboard to improve quality and durability. When the paper is later recycled or becoming new paper, the coatings may pollute the water used in the recycling process. Thus, it is important to know in which fraction these coatings finish during the process. In this study, laboratory made samples that mimic the repulping and paper making process is used. The different fractions of the processes were analyzed for a clay as well as a polymer coating. Metal content from clay coating is analyzed using inductively coupled plasma-mass spectrometry and microwave plasma-atomic emission spectrometry. For analyzing polymer coating, gas chromatography-mass spectrometry was used. From the result of the analysis the Reject sample, which was collected with a bigger mesh sieve in a repulping system, contained the highest amount of both clay and polymer coating. The other sample fractions from the repulping process and paper making process, did not contain as high mass content of either clay nor polymer coating.
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Fluoride removal by low-cost adsorbentsBernheim, Fredrik January 2022 (has links)
Fluoride, the most abundant form of fluorine, is an ion released into the environment, mainly via anthropogenic sources and erosion of mineral rocks. Although the element is well known for its health benefits on teeth and bones, it can as well be a harmful pollutant. In some areas on earth, the population can not obtain drinking water that is below the guideline limits of fluoride, which is set to 1.5 mg/L by the world health organization (WHO). Therefore there is a relevance to develop methods that can clean the waters from excess fluoride. The potential problems when it comes to finding these types of methods is that they can be expensive. However, materials generated as residues in industrial processes may be low in cost. In this thesis, silicon reduced AOD-slag, a material generated as a by-product from the production of stainless steel, was examined by its fluoride adsorption behavior and adsorption capacity. The concentrations of fluoride were measured with ion chromatography (IC) and the concentration of metals were analyzed with microwave plasma atomic emission spectroscopy (MP-AES). Additionally pH and conductivity were measured. The functionality of the material surface was analyzed with isotherm modeling, where the Sips isotherm model was tested. Moreover, optimization of the slag was performed by heat treating the material, as well as a sorption kinetics test on both optimized and original slags. The results from the analysis indicated that the material corresponds well to the Sips isotherm. Considering this result it is suggested that at low concentrations, the surface can be characterized as heterogeneous, with different binding energies at different available sites. At higher concentrations the Sips-model explains the surface to be saturated when a monolayer of fluoride is formed. Therefore the binding on the slag surface can be described to have an inner-sphere and covalent character. The metal analysis showed that calcium ions are released from the slag when in aqueous solutions. The presence of calcium in the liquid samples are believed to result in formations of solid calcium fluoride (CaF2), precipitated on the slag surface. Lastly, the maximum fluoride removal is believed to differ between different types of AOD-slag, where there as well are possibilities to optimize the material.
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Comparison of MP-AES and ICP-MS for thedetermination of potentially toxic elements in (polluted) plant materialBaysal, Ramazan January 2024 (has links)
The purpose of this study was to assess the metal content present in pine needles collected from an old shooting range known for elevated lead levels in the soil by different analytical methods. The focus on conifers originated from their evergreen nature year-round, and their ability to absorb potentially harmful elements. Research on needles as biomonitors for environmental contamination, particularly in areas affected by heavy metal pollution, has gained significant global attention. Four trees, two Norway spruces (Picea abies), and two Scots pines (Pinus sylvestris) were identified within the designated area. Samples of conifer needles were collected in plastic bags. The needles underwent washing, drying, and grinding into powder for subsequent digestion method and quantitative determination of metal content using ICP-MS and MPAES. The study focused on elements commonly found in various types of ammunition, specifically manganese, iron, nickel, copper, zinc, molybdenum, antimony, and lead. Results obtained from both analytical methods, which was only manganese, showed statistically significant differences. During the analysis, only manganese could be quantified using MPAES, as the other analytes were below the detection limit. For ICP-MS, the LOD values were much lower, making this method more suitable, as all analytes were above LOD and could be quantified. The recovery values for the CRM were good for all elements when ICP-MS was utilized. However, the calculated recovery value for manganese decreased based on the results obtained from MPAES compared to the calculated recovery value for manganese based on the results obtained from ICP-MS. Interestingly, the analysis of conifer needles revealed no noticeable contamination from the shooting range. Instead, it highlighted variances among different pine needle species. The metal content in the pine needles remained within acceptable limits according to external literature sources.
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