Recent studies have shown increasing levels of unidentified fluorinated compounds, with unknown toxic effects to living organisms. These unidentified fluorinated compounds might be those novel replacements for PFOS and PFOA and some other related chemicals. These fluorinated substances have proven to be a challenge to identify and measure in blood samples and the number has been approximated to over 4700 compounds. Analysing the extractable organic fluorine (EOF) in samples and performing a mass balance analysis on measurable per- and polyfluoroalkyl substances (PFAS) to total EOF can provide an estimate on the levels of unidentified fluorinated compounds.Following the contamination of drinking water in Ronneby, a third of the population in the affected area were exposed to elevated levels of PFASs. PFHxS, PFOS and PFOA were measured in serum samples. The present study measured 11 target PFAS as well as EOF in whole blood samples from Ronneby (with known exposure) together with samples from three other cities in Sweden to preform a mass balance analysis in order to estimate the levels of unidentified fluorinated compounds. Results showed measurable concentrations of 11 PFAS in all cities included in this study, and mass balance analysis of EOF indicated the presence of unidentified fluorinated compounds in all samples, ranging from 47 % to 89 % among the samples from Ronneby and 11 % to 42 % among samples from Stockholm, Örebro and Malmö. The composition of 11 PFAS in human blood samples might indicate the source of exposure.

Aeration tests were conducted under non-standard conditions with clean tap water in various temperatures below 20 °C, with the aim of studying changes that may occur. An initial deoxygenation of 0.8 litre water was performed with sodium sulfite and a cobalt catalyst pre-dissolved in water, in order to bind already present dissolved oxygen. The resulting dissolved oxygen concentration after 20 minutes did not decrease below 2 mg/L, despite increasing the sodium sulfite concentrations. Thereafter, a reoxygenation with the same time interval was conducted by using an aeration system, which resulted in an increase of saturated oxygen concentration with lower temperatures. pH-measurements were carried out during the whole experiment in order to follow the conversion of sulfite to sulfate. The pH-data obtained confirmed that sulfite had been converted to sulfate, although, a few deviations could be observed for most of the experiments. The conductivity was also measured to ensure that the sulfite had been properly dissolved when added to the water tank. In general, the conductivity never deviated and held a constant trend throughout the tests. The collected data could not be made of use in order to properly determine how the aeration, for temperatures below 20 °C, could be evaluated. Further tests have to be performed in order for a definite conclusion to be drawn.

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All around the world the environmental focus is growing rapidly.The aim of thismaster’s thesis has been to work on developing experimental methodologies to achieve qualitatively, reliable and optimal data used on modelling. The selected study case is the analysis of ammonia adsorption on a V-SCR catalyst, which is an important step for future SCR-performance. Over the last years the mechanism of the V-SCR catalyst and the nature of its active sites have been widely discussed in order to be understood. However, so far, no clear conclusionshavebeen established about the catalytic mechanism, particularly on atomic level,thatdemonstrates the complexity of the catalytic chemistry within the SCR process. The kinetics of the adsorption of ammonia on a commercial V-SCR catalyst needs further investigation and much more knowledge is neededto understand the chemistry and the behavior behind it. In order to obtain this, new methods where high-quality data is achievedfor the adsorption phenomenon, need to be developed.The results from this workhas demonstrated the used method to be a reliable way to ensure reproductively dataat each temperature used for ammonia adsorption performed over a V-SCR catalyst. Further work with focus on the in-depth of the kinetics in the adsorptionprocessis needed.It is necessary toenhance the understanding ofthe behaviour of theadsorption on theactive sitesof the V-SCR catalyst surface as well as performing tests with lowerammoniaconcentrations for an even better understandingof the processes. / Över hela världen växerfokus på miljön snabbt. Insikten om behovet av att minska föroreningar och avgaser kräver nya lösningar inommånga områden. Syftet med examensarbetethar varit att utveckla experimentella metoder för att säkerställa att data som används vid modellering erhåller enbra kvalitet, är pålitlig och optimal. Det valda studiefallet har varit att analysera ammoniakadsorptionen på en V-SCR-katalysator, vilket är ett viktigt steg för SCR-prestandan.Under de senaste åren har mekanismen för V-SCR-katalysatorn och naturen av dess aktiva säten diskuterats i stor utsträckning för att bättre kunna förstås. Hittills har ingen klar slutsats etablerats om den katalytiska mekanismen, speciellt på atomnivå,vilket visar på komplexiteten iden katalytiska kemin inom SCR-processen. Kinetiken för adsorption av ammoniak på en kommersiell V-SCR-katalysator behöver undersökas ytterligare och mer kunskap behövs för att förstå kemin och beteendet bakom. För att uppnå detta måste nya metoder utvecklas där högkvalitativa data uppnåsfrån adsorptionen av ammoniaken på en V-SCR katalysator. Resultaten från detta arbete har visat att den valda metoden är ett tillförlitligt sätt att säkerställa reproduktivt datavid varje temperatur som används för den studerade adsorptionen av ammoniak på en V-SCR katalysator. Ytterligare arbete krävsmed störrefokus på djupet av kinetiken inomadsorptionsprocessen. Detta för att öka förståelsen för beteendet hosadsorptionen på de aktiva sätenahos ytan på V-SCR katalysatornsamt utförande av test med lägrekoncentration av ammoniak förenännu bättre förståelse.

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