Philosophiae Doctor - PhD (Chemistry) / Lithium ion capacitors are new and promising class of energy storage devices formed from a combination of lithium-ion battery electrode materials with those of supercapacitors. They exhibit better electrochemical properties in terms of energy and power densities than the above mentioned storage systems. In this work, lithium manganese oxide spinel (LiMn2O4; LMO) and lithium manganese phosphate (LiMnPO4; LMP) as well as their respective nickel-doped graphenised derivatives (G-LMNO and G-LMNP) were synthesized and each cathode material used to fabricate lithium ion capacitors in an electrochemical assembly that utilised activated carbon (AC) as the negative electrode and lithium sulphate electrolyte in a two-electrode system. The synthetic protocol for the preparation of the materials followed a simple solvothermal route with subsequent calcination at 500 - 800 ?C. The morphological, structural and electrochemical properties of the as prepared materials were thoroughly investigated through various characterisation techniques involving High resolution scanning electron microscopy (HRSEM), High resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), Small-angle X-ray scattering (SAXS), Electrochemical impedance spectroscopy (EIS), Cyclic voltammetry (CV) and Galvanostatic charge/discharge.

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The product R1-MR2E is an ester formed from an esterification of a carboxylic acid and an alcohol at Cambrex Karlskoga AB. The production of the intermediate R1-MR2E is a large-scale production and there are two main objectives and two sub-objectives that this project aims to study of the manufacturing.The manufacturing of R1-MR2E experience big variations in the product yield which is affecting theproductions stability and economic aspects of it. Thus, one of the main objectives in this project was to use experimental design to find significant factors that causes yield variations. The results from this study showed five significant factors that affect the yield positively or negatively by resulting in higher or lower product weight. The factors found are the amount of charged toluene solution containing the by-product R1-DR2E from the recycling system, the amount of charged carboxylic acid, the reaction time, the amount of added Na2SO3 in the neutralisation step and the regulated pH value after the crystallisation step. The other main objective is to optimize the purification sub-section using activated carbon (AC). There are two sub-objectives for this part of the study where the first sub-objective is to evaluate how much activated carbon that is needed to remove the impurities and colouration in the product. The second sub-objective is to investigate if an activated carbon filter could be used as a substitute for the commonly used loose powder activated carbon. To answer this objective a laboratory method was used, where the large-scale purification- and crystallisation step as well as after treatment were scaled down to lab scaleand then experiments were conducted to determine the effects of different amounts of activated carbon, using no carbon, and utilizing another type of activated carbon known as activated carbon filters. The results were then analysed for colour and purity by a visual observation method and High-Performance Liquid Chromatography (HPLC) method. The conclusion from this study is that only 25% of the amount of activated carbon used today is needed to remove the colouration in the product. The activated carbon did not completely remove the impurities in the product. The other conclusion was that the idea that the activated carbon removed the small impurities was wrong, and the levels of the impurities are already small enough in the large-scale production that the purification step is not needed to reach approved levels of these impurities. The activated carbon filter also works to remove the colouration with only one filtration but does not work well on removing the impurities in the product. / Produkten R1-MR2E är en ester som formas med en förestring av en karboxylsyra och en alkohol på Cambrex Karlskoga AB. Produktionen av intermediet R1-MR2E är en storskalig produktion och det finns två huvudmål och två delmål som studeras i studien. Produktionen av R1-MR2E upplever stora variationer i produktsutbytet vilket påverkar produktionensstabilitet och ekonomiska aspekter. Ett av målen med detta projekt är därmed att använda experimentell design för att hitta signifikanta faktorer som orsakar utbytesvariationer. Resultatet från den här studien visar på fem faktorer som påverkar utbytet positivt eller negativt genom att bidra till högre eller lägre utpackad vikt. Faktorerna som hittades är mängden av den satsade R1-DR2E från återvinningssystemet, mängden av den satsade karboxylsyran, reaktionstiden, mängden av den adderade Na2SO3 under neutralisation steget och de reglerade pH efter kristallisations steget. Det andra målet är att optimera ett av produktionens delsteg, rening med aktivt kol (AC). Det finns två delmål för den delen av studien, de två delmålen är att ta reda på hur mycket aktivt kol som behövs för att ta bort föroreningar och förbättra färgen i produkten samt undersöka om aktivt kolfilter kan användas som ett substitut för det vanligen använda lösa aktiva kolpulver. För att genomföra det här målet så användes en laborativ metod, där det storskaliga renings- och kristallisationssteget samt efterbehandling skalades ner till laborativ skala. Sedan genomomfördes experiment för att bestämma effekten av olika mängder aktivt kol, inget aktivt kol, och använda en annan typ av aktivt kol i formen av ett aktivtkolfilter. Resultaten från det laborativa arbetet analyserades sedan med en visuell metod samt högpresterande vätskekromatografisk (HPLC) metod. Slutsatsen från studien är att bara en 25% av den mängd aktivt kol som används i dagens läge behövs för att ta bort färgen i produkten. Det aktiva kolet tog dock inte bort föroreningarna i produkten speciellt bra. Det betyder att idén om att det aktiva kolet tar bort föroreningar är fel och att nivåerna av föroreningarna redan är tillräckligt låga i den storskaligaproduktionen för att bli godkända i koncentration utan reningssteget. AC filter fungerar också för att ta bort färgen med endast en filtrering men fungerar inte att använda för att ta bort föroreningarna i produkten.

Arbetet studerade skillnaderna mellan en användning av kalciumhydroxid samtnatriumhydroxid som pH-reglerande kemikalie i en kemisk vattenreningsanläggning.Samt dess påverkan på filtreringssteg som sandfilter, aktivkol filtrering samt jonbytarfiltrering. Det behandlade hur reningsgraden påverkas sett till metallreduktion av;krom, nickel, koppar och zink. Hur slammängderna är i förhållande tillvarandramellan de olika pH-reglernade kemikalierna och slutligen hur filtreringsstegenpåverkas beroende på vilken pH-reglerande kemikalie som doserats. Resultatet förarbetet har visat på att reningsgraden minskar vid användning av natriumhydroxidsom pH-reglerande kemikalie vilket besvarar en del av syftet samt frågeställningenmed arbetet. Ytterligare har resultatet påvisat att de efterkommande filtreringsstegensom i en eventuell framtid kan implementeras leder till en reducering avmetallhalterna i vattnet, vanligen gick reduceringen inte att statistiskt säkerställa mentendenser på en reducering påvisades. Även de erhållna slammängdernareducerades vid användning av natriumhydroxid som pH-reglerande kemikalie vilketvar ett förväntat resultat sett till hypotes och litteratur. Ytterligare minskadeturbiditeten för klarfasproverna vid en natriumhydroxiddosering i förhållande till enkalciumhydroxiddosering. Arbetets resultat har således påvisat den goda möjlighetenatt ersätta den manuella doseringen av solid kalciumhydroxid som pH-reglerandekemikalie emot en automatisk dosering av natriumhydroxid erhållen i vätskeform. / This work studied the differences between the use of calcium hydroxide and sodiumhydroxide as a pH-regulating chemical in a chemical water treatment plant. As wellas its impact on filtration steps such as sand filter, activated carbon filtration and ionexchange filtration. It dealt with how the degree of purification is affected in terms ofmetal reduction of; chromium, nickel, copper and zinc. How the sludge amounts arein relation to each other between the different pH-regulated chemicals and finallyhow the filtration steps are affected depending on which pH-regulating chemical hasbeen dosed. The results for the work have shown that the degree of purificationdecreases when using sodium hydroxide as a pH-regulating chemical, whichanswers part of the purpose and the question of the work. Furthermore, the resultshave shown that the subsequent filtration steps that can be implemented in thepossible future lead to a reduction of the metal contents in the water, usually thereduction could not be statistically confirmed but tendencies of a reduction wereshown. The amounts of sludge obtained were also reduced by using sodiumhydroxide as a pH-regulating chemical, which was an expected result in terms ofhypothesis and literature. Furthermore, the turbidity of the clear phase samplesdecreased at a sodium hydroxide dosage relative to a calcium hydroxide dosage.The results of the work have thus demonstrated the good possibility of replacing themanual dosing of solid calcium hydroxide as a pH-regulating chemical with anautomatic dosing of sodium hydroxide obtained in liquid form.

There is a current lack of accurate tools to determine the concentration of cyanobacteria in situ.  Besides, cyanobacterial blooms have to be carefully monitored in reservoirs as they are more frequent because of climate change and can lead to potential released of toxins, along with other components. This project investigates the possible use of fluorescent probes to measure the concentration of different types of organic matter released by the algae. Three different species of toxic cyanobacteria were chosen to carry out this research as they are representative of the local harmful blooms found across Australia. Furthermore, the efficiency of two different chemicals (powdered activated carbon, also known as PAC, and alum) used in drinking water treatment plants were investigated, in order to determine a method for automatic dosage adjustment in water treatment plant. The organic matter was characterized by LC-OCD and fluorescence spectroscopy and statistical analysis such as principal component analysis was performed on the generated data. General characterization of the different species was firstly performed and globally, similar comportments were observed among the three cyanobacteria species. There is indeed a general increase in the release of organic material throughout the cell’s growth phase. Results from the jar tests showed that PAC mainly targeted humic-like substances and building blocks, which are middle size particles. The average removal rate obtained was 40µg/L per mg/L of PAC added into the water. Therefore, there is indication that the decreased efficiency for the removal of the taste and odor compounds observed in certain plants can be partially attributed to direct competition of organic matter adsorption onto PAC instead of a blockage of the PAC pores by larger particles. On the other hand, alum was able to remove large particles, particularly biopolymers and also humic-substances. However, a great increase of the low molecular weight molecules at very high doses of alum was seen, which suggest that a too high dose of alum is toxic for the algae cells. Based on the bench scale testing the recommended dose of 50 mg/L seems to be optimum for the studied water treatment plant. Specific ultraviolet absorbance and dissolved organic carbon measurements were also investigated and good correlations were found between the concentration of humic-like substances and absorbance, confirming that they are good measure to assess the content of organic matter in the water. However, as the slope coefficient of the linear trend varied between the species, it was not possible to obtain a common conversion factor for all the species. Finally, one fluorophore was found in common to all the samples and is characterized by the excitation-emission wavelength: 240/440 nm. Correlations with the chromatography’s results were investigated and this component seems to match the biopolymers and humic-like substances concentrations. Furthermore, its intensity decreases continuously with the addition of PAC whereas a drop was observed at the lower doses of alum. In regards on these findings, a method for automatic chemicals dosing from the fluorescence measures was proposed. / Detta examensarbete handlar om hur dricksvattenkvalitet kan kontrolleras och övervakas i vattenreningsverk. Nu existerar  inte någon exakt metod för att bestämma koncentrationen av cyanobakterier i vatten då det finns många olika arter. Men det är viktigt att övervaka algers tillväxt in i vattenreningsverk för de kan släppa ut skadliga ämnen till dricksvattnet. De tre arter som studerats i detta projekt är giftiga. Det organiska materialet i råvattnet kan också blockera membranporer eller leda till n biprodukter, som är cancerframkallande. Till sist konkurrerar några organiska substansen med smak- och luktföreningar för adsorptionsställena hos det pulverformiga aktiverade kolet. Därför är smaken och luktföreningarna inte väl borttagna, vilket leder till kundernas klagomål. Cyanobakterier måste övervakas noggrant.                            För att bestämma biologisk och kemisk egenskap hos vatten används flera tekniker för närvarande. I examensarbetet har undersökningar med vätskekromatografi och fluorescensteknik företagits. Kromatografi användes för att klassificera den organiska substansen i mindre grupper: biopolymerer, humus substanser, byggstenar och neutralmolekyler med låg molekylvikt (LMVN). Statistisk analys med R, inklusive huvudkomponentanalys företogs på insamlade data. Fluorescensdata registrerades också och visas i en excitationsutsläppsmatris.                            Experimenten reproducerade en behandlingsprocess och undersökte effektiviteten hos två kemikalier: pulveriserat aktivt kol (PAK) och alun. Resultaten visade att humusämnen   och dess byggstenar var väl borttagna av PAK medan även biopolymerer och humusämnen var väl bortagna av alun. Emellertid var en för hög dos av alun skadlig eftersom det ledde till en ökad frisättning av LMVN. I synnerhert kunde PAK ta bort 40µg/L av både humusämnen och dess byggstenar per mg/L av PAK tillagd. Det föreslår att de är de viktigaste konkurrenterna och att endast direkt konkurrens för adsorptionsställena sker. Om det fanns blockeringsfenomen, skulle det också finnas en minskning för biopolymererna. Den optimala doseringen av alun som bestämdes för det undersökta vattenreningsverket var 50 mg/L. Det kunde ta bort 60-70% av biopolymerer och 40-50% av humusämnen.                            Specifik ultraviolett absorbans och fluorescens registrerades. Båda visade riktigt bra korrelationer med humusämnen, vilket gör de till bra verktyg för att bedöma vattenkvaliteten. Men det kräver fortfarande att arten av cyanobakterie urskiljs eftersom koefficientens lutningar var olika. De kan därför vara ett verktyg för att mäta koncentrationen av organisk material, men arten måste vara känd. Fluorescencedata visade en topp vid 440 nm. En parallellfaktoranalys utfördes på data och endast en komponent hittades gemensam i alla prover. Därför studerades den maximala fluorescensintensiteten hos denna komponent. Å ena sidan kunde vi observera en kontinuerlig minskning av intensiteten när PAK tillsattes. Det är därför möjligt att veta hur man justerar den kemiska doseringen från fluorescensintensiteterna. I slutet av examensarbetet föreslås en metod för automatisk kemisk dosering. Fluorescensprober kan ännu inte exakt indikera cellkoncentrationen. Men med flera sonder som riktar sig till olika våglängder kan de redan vara till stor hjälp för styrning vid vattenverk.

This dissertation reports on research related to ultrafiltration (UF) membranes in drinking water applications. A pilot-scale investigation identified seasonal surface water quality impacts on UF performance and resulted in the development of a dynamic chemically enhanced backwash protocol for fouling management. Subsequent analysis of UF process data revealed limitations with the use of specific flux, transmembrane pressure (TMP), and other normalization techniques for assessing UF process fouling. A new TMP balance approach is presented that identifies the pressure contribution of membrane fouling and structural changes, enables direct process performance comparisons at different operating fluxes, and distinguishes between physically and chemically unresolved fouling. In addition to the TMP balance, a five component optimization approach is presented for the systematic improvement of UF processes on the basis of TMP variations. Terms are defined for assessing process event performance, a new process utilization term is presented to benchmark UF productivity, and new measures for evaluating maintenance procedures are discussed. Using these tools, a correlation between process utilization and operating pressures was established and a sustainable process utilization of 93.5% was achieved. UF process capabilities may be further enhanced by pre-coating media onto the membrane surface. Silicon dioxide (SiO2) and powdered activated carbon (PAC) are evaluated as precoating materials, and the applicability of the TMP balance for assessing pre-coated membrane performance is demonstrated. The first use of SiO2 as a support layer for PAC in a membrane pre-coating application is presented at the laboratory-scale. SiO2-PAC pre-coatings successfully reduced physically unresolved fouling and enhanced UF membrane organics removal capabilities.

Stormwater is a significant transport medium for pollutants to recipients located near cities. Substances commonly found in stormwater include nutrients, metals, organic substances and particles. A group of pollutants detected in stormwater are per- och polyfluoroalkyl substances (PFAS). PFAS is a group of chemicals which have been proven to have harmful effects on health, such as endocrine disruptive effects. The most sensitive considered parameter today is effects on the immune system, but a few of these substaces are also classified as carcinogenic or potentially carcinogenic. The distribution of PFAS to the environment is significant from both new and historical uses and sources, which continue to contribute to the environment due to high persistence of PFAS. The most significant point sources of PFAS in stormwater are industrial processes and manufacturing of PFAS-containing products, firefighting foam and hydraulic oil. Atmospheric deposition, building materials and traffic also contribute but in a smaller scale.  This thesis is based on a case study of a Swedish stormwater system and is aimed to evaluate which concentrations that can be classified as elevated in the stormwater system. Another aim is to investigate various remedial measures against the elevated levels of PFAS in the stormwater system. This was accomplished by a literature study of remediation techniques for PFAS applicable to a case study of an investigated stormwater system. The case study was carried out in different parts to estimate the risks and possible measures. The parts were action levels, site-specific guideline values, sampling, requirements for actions or remediation, and possible remediations techniques. Action targets and site-specific guideline values were developed based on literature and results obtained using a conceptual model. The action target was stated as follow: Stormwater must not contribute to the distribution of per- och polyfluoroalkyl substances which in a long term can result in levels in surface water that pose a risk to human health. The site-specific guideline value of 4,4 ng/L PFOA-equivalents at the outlet of the storwater, was developed based on background levels and environmental quality standards from EU:s water directive for surface water.  Sampling and analysis of 22 different PFAS compounds was carried out at 10 different sampling locations in the actual stormwater system of the case study. The measured levels were compared to the site-specific guideline value, and an assessment of requirements for actions or remediation was carried out. The measured levels in the stormwater system were calculated, 5,76 ng/L PFOA-equivalents. Finally, an investigation was done of possible remedial actions and suitable remediations techniques. The stormwater system needed further investigations to make a legitimate decision about the need for stormwater treatment of PFAS. Investigations of potential point sources were suggested as adequate in order to apply the most resource efficient remedial action. Various remedial techniques were also considered for the stormwater system. The techniques were evaluated based on the criterias's; remedial capacity, water matrix, estimations of captial- and operating costs, energy requirements and availability on the market.

The fast pyrolysis plant at RISE – ETC, Piteå produces carbon rich chars in bulk from various sources of biomass as feedstock. These in-house manufactured carbon rich chars were upgraded via pyrolysis as well as chemical activation using KOH to enhance their potential as an electrode material for supercapacitors. Commercial activated charcoal (Merck) was also studied and used as a yardstick for comparing performance of our materials. Investigations using EDX show enrichment in carbon content and very low amounts of impurities in the materials prepared from wood char after specific treatments for upgrading. Two-electrode coin cell apparatus with an aqueous electrolyte was used to determine the electrochemical performance of these materials. Wood char after KOH activation shows a high specific capacitance of ~105 Fg-1 at 2 Ag-1 in galvanostatic charge discharge measurements which outperformed activated charcoal used in this study (~68 Fg-1 at 2 Ag-1). This material was tested in a wide range of conditions (current density ranging from 0.1 Ag-1 to 10 Ag-1) and showed specific capacitance from ~90 Fg-1 (for 10 Ag-1) up to ~118 Fg-1 (for 0.1 Ag-1). Fatigue testing for >20000 cycles showed a remarkably high retention (>96%) of capacitance. Currently, most commercial supercapacitors use activated carbon materials prepared from coconut shells as the active electrode material which are not native to Sweden. In this study, we upgrade wood chars produced at RISE – ETC from biomass sources obtained locally (Sweden and Scandinavia) and demonstrate their applicability as supercapacitor electrode materials. / Den snabba pyrolysanläggningen vid RISE - ETC, Piteå, producerar kolrika kol i bulk från olika källor till biomassa som råvara. Dessa interna tillverkade kolrika karaktärer uppgraderades via pyrolys samt kemisk aktivering med hjälp av KOH för att förbättra deras potential som ett elektrodmaterial för superkondensatorer. Kommersiellt aktivt kol (Merck) studerades och användes som en måttstock för att jämföra våra materials prestanda. Undersökningar med EDX visar berikning av kolinnehåll och mycket låga mängder föroreningar i material som framställts av träkol efter specifika behandlingar för uppgradering. Tvåelektrodmyntcellapparater med en vattenhaltig elektrolyt användes för att bestämma den elektrokemiska prestandan hos dessa material. Träkol efter KOH-aktivering visar en hög specifik kapacitans på ~ 105 Fg-1 vid 2 Ag-1 i galvanostatiska laddningsurladdningsmätningar som överträffade aktivt kol som användes i denna studie (~ 68 Fg-1 vid 2 Ag-1). Detta material testades under ett stort antal betingelser (strömtäthet från 0,1 Ag-1 till 10 Ag-1) och visade specifik kapacitans från ~ 90 Fg-1 (för 10 Ag-1) upp till ~ 118 Fg-1 (för 0,1 Ag-1). Trötthetstestning för > 20000 cykler visade en anmärkningsvärt hög retention (> 96%) av kapacitansen. För närvarande använder de flesta kommersiella superkondensatorer aktivt kolmaterial framställt av kokosnötskal som det aktiva elektrodmaterialet som inte är hemma i Sverige. I den här studien uppgraderar vi träkolor som produceras vid RISE - ETC från biomassakällor erhållna lokalt (Sverige och Skandinavien) och visar deras användbarhet som superkapacitorelektrodmaterial.

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