Recovery of carboxylic acids from aqueous solutions

Carboxylic acids are commonly used organic acids and have many applications in industries producing food and pharmaceutical products, surfactants and detergents. Especially formic, acetic, propionic and butyric acid are important organic chemicals. These compounds can be found in many side streams and plant effluents. Recovery costs of carboxylic acids are high when they are removed from dilute solution. Conventional processes for the recovery of carboxylic acids from aqueous solutions are classical distillation or extractive distillation, azeotropic distillation or liquid-liquid extraction. The literature part of this Master’s of Science Thesis comprises possible extractants in liquid-liquid extraction of carboxylic acids from aqueous solutions and methods for their regeneration form the extract. The experimental part of this Thesis investigates liquid-liquid extraction of carboxylic acids from aqueous solutions. The aim of this work was to find a suitable extractant for liquid-liquid extraction and suitable process conditions to recover carboxylic acids from aqueous solutions. Also, back extraction of carboxylic acids and their thermal decomposition in relation to distillation of were. Experiments showed that there is more than one possible extractant for liquid-liquid extraction of carboxylic acids. Results also showed that it is possible to separate carboxylic acids and regenerate all the used extractants by vacuum distillation at suitable temperature.

Pohjoiset maisemat : "Eurooppalaisen maisemayleissopimuksen toteuttaminen Pohjois-Kalotin kunnissa" - Konferenssi Inarissa 7.-9.9.2011

Kansainvälinen Eurooppalaisen maisemayleissopimuksen tavoitteiden saavuttamista edistävä konferenssi järjestettiin Inarissa 7.-9.9.2011. Konferenssissa käsiteltiin maisemasopimuksen tavoitteita, tarpeita ja mahdollisuuksia Pohjois-Kalotin alueella. Tähän raporttiin on koottu konferenssissa esiintyneiden asiantuntijoiden laatimat artikkelit aiheesta. Raportin toivotaan helpottavan alueiden käytön suunnittelijoita käytännön työssään ja rohkaisevan kuntia toteuttamaan tulevaisuuden suunnittelua Eurooppalaisen maisemayleissopimuksen tavoitteiden mukaisesti. Raportti on saatavissa viidellä eri kielellä: suomeksi, ruotsiksi, norjaksi, pohjoissaameksi ja englanniksi. Pohjois-Kalotin aluetta yhdistää yhteinen tunnusomainen maisema. Saamelaiskulttuurin sekä poronhoidon muovaamat tunturimaisemat ja upeat jokivarsimaisemat heijastuvat ympäristössä laaja-alaisesti. Alueen maisemalle haasteita tuovat sen moninaiset maankäyttömuodot ja elinkeinot, kuten matkailu, kaivosteollisuus ja energiantuotanto. Arvokkaiden maisemapiirteiden säilyttäminen vaatii erityistä tuntemusta ja tietämystä alueen kunnissa. Maisemansuojelua ja -hoitoa toteutetaan alueiden- ja maankäytön suunnittelun kautta, pääasiallisesti kaavoituksella ja maisemanhoitosuunnitelmilla. Pohjois-Kalotin alueen kunnissa on erilaiset osin toisistaan poikkeavat toimintatavat ja käytännöt maisemanhoidossa. Kuitenkin alueen asukkailla on yhtäläisiä intressejä elinympäristönsä suojeluun ja säilyttämiseen. Maisema nähdään vetovoimatekijänä, jota ei haluta menettää. Lisääntyvät maankäyttötarpeet kunnissa luovat tarpeen entistä moniulotteisemmalle suunnittelulle. Paikallisten tahojen osallistaminen suunnitteluprosesseihin aikaisessa vaiheessa ja monimuotoinen vuorovaikutus, niin toimijoiden, kansalaisten kuin viranomaisten välillä vähentää konfliktien muodostumista. Tutkimustiedon tehokkaampi hyödyntäminen ja valtiorajat ylittävä yhteistyö helpottaa päätöksentekoa ja luo yhteisiä linjoja maisemansuojelutyöhön. Yhteiset kokemukset, käytännöt ja tietotaidon jakaminen sekä laajemman maisemakokonaisuuden hahmottaminen parantaa eurooppalaisen maisemayleissopimuksen tavoitteiden toteutumista. Työn jatkuvuuden varmistamiseksi Pohjois-Kalotin alueelle suunnitellaan perustettavaksi maisemayhteistyöryhmä, jonka tehtävä on maisemapolitiikan kehittäminen ja eteenpäin vieminen.

Northern Landscapes : ʻʻImplementation of the European Landscape Convention In the North Calotte Area Municipalitiesʼʼ - Conference in Inari, Finland 7-9.9.2011

The conference promoting the objectives of the international European Landscape Convention (ELC) was held on 7-9 September 2011 in Inari. The primary aim of the conference was to increase awareness of the ELC and the prospects and requirements it brings to practical planning work, especially at the municipal level. The conference speakers included top experts from Sweden, Norway, Finland, France, Holland and Catalonia. This report is a collection of articles written by the experts in the ELC conference. The report is available in five languages: Finnish, Swedish, Norwegian, Northern Sámi and English. The common characteristics of the North Calotte area, such as the magnificent riverside scenery and the beautiful fell landscapes formed by the Sámi culture and reindeer management are broadly reflected in the environment. Alongside the traditional forms of land use, many other livelihoods and forms of land use now need to be accommodated in the area. Tourism, energy production, mining industry and new infrastructure create new and manifold challenges to the authorities in charge of land use in these areas. Municipalities need information and support for versatile planning in the future, so that the unique and valuable characteristics of the North can be preserved. Landscape protection and management in the landscape areas is executed through areal and land use planning, mainly through town planning and the creation of landscape management plans. The municipalities in the North Calotte region have their own partly divergent methods and practices, based on the various land use processes are executed. The municipalities and inhabitants have a great interest in preserving and protecting their living environment and maintaining and increasing the appeal of the area. Landscape is viewed as one of the most significant appealing factors that cannot be lost. The increasing land use in municipalities, for example due to energy production, mining industry and increasing tourism, create a need for more multidimensional planning. The reconciliation of the wishes of different interest groups, and traditional and new livelihoods will not be easy. Conflict is inevitable. This will lead to a greater need to engage local bodies to the planning processes right from the start of the projects. Close cooperation between different administrative branches, operators, local bodies and landscape research promote the objectives of the convention. To ensure that the work continues, a landscape co-operation group is planned to be established in the North Calotte area. It´s main task is to promote and develop landscape policy in the area.

Landskapet i nord : ”Gjennomføring av Den europeiska Landskapskonvensjonen i kommunene på Nord-Kalotten” – Konferansen 7.-9. 9.2011, Enare, Finland

Kansainvälinen Eurooppalaisen maisemayleissopimuksen tavoitteiden saavuttamista edistävä konferenssi järjestettiin Inarissa 7.-9.9.2011. Konferenssissa käsiteltiin maisemasopimuksen tavoitteita, tarpeita ja mahdollisuuksia Pohjois-Kalotin alueella. Tähän raporttiin on koottu konferenssissa esiintyneiden asiantuntijoiden laatimat artikkelit aiheesta. Raportin toivotaan helpottavan alueiden käytön suunnittelijoita käytännön työssään ja rohkaisevan kuntia toteuttamaan tulevaisuuden suunnittelua Eurooppalaisen maisemayleissopimuksen tavoitteiden mukaisesti. Raportti on saatavissa viidellä eri kielellä: suomeksi, ruotsiksi, norjaksi, pohjoissaameksi ja englanniksi. Pohjois-Kalotin aluetta yhdistää yhteinen tunnusomainen maisema. Saamelaiskulttuurin sekä poronhoidon muovaamat tunturimaisemat ja upeat jokivarsimaisemat heijastuvat ympäristössä laaja-alaisesti. Alueen maisemalle haasteita tuovat sen moninaiset maankäyttömuodot ja elinkeinot, kuten matkailu, kaivosteollisuus ja energiantuotanto. Arvokkaiden maisemapiirteiden säilyttäminen vaatii erityistä tuntemusta ja tietämystä alueen kunnissa. Maisemansuojelua ja -hoitoa toteutetaan alueiden- ja maankäytön suunnittelun kautta, pääasiallisesti kaavoituksella ja maisemanhoitosuunnitelmilla. Pohjois-Kalotin alueen kunnissa on erilaiset osin toisistaan poikkeavat toimintatavat ja käytännöt maisemanhoidossa. Kuitenkin alueen asukkailla on yhtäläisiä intressejä elinympäristönsä suojeluun ja säilyttämiseen. Maisema nähdään vetovoimatekijänä, jota ei haluta menettää. Lisääntyvät maankäyttötarpeet kunnissa luovat tarpeen entistä moniulotteisemmalle suunnittelulle. Paikallisten tahojen osallistaminen suunnitteluprosesseihin aikaisessa vaiheessa ja monimuotoinen vuorovaikutus, niin toimijoiden, kansalaisten kuin viranomaisten välillä vähentää konfliktien muodostumista. Tutkimustiedon tehokkaampi hyödyntäminen ja valtiorajat ylittävä yhteistyö helpottaa päätöksentekoa ja luo yhteisiä linjoja maisemansuojelutyöhön. Yhteiset kokemukset, käytännöt ja tietotaidon jakaminen sekä laajemman maisemakokonaisuuden hahmottaminen parantaa eurooppalaisen maisemayleissopimuksen tavoitteiden toteutumista. Työn jatkuvuuden varmistamiseksi Pohjois-Kalotin alueelle suunnitellaan perustettavaksi maisemayhteistyöryhmä, jonka tehtävä on maisemapolitiikan kehittäminen ja eteenpäin vieminen.

Davviduovdagat : ”Eurohpálaš duovddaoktasašsoahpamuša ollašuhttin Davvikalohta gielddain” Konfereansa čakčamánu 7.-9. beaivve 2011, Anár, Suopma

Kansainvälinen Eurooppalaisen maisemayleissopimuksen tavoitteiden saavuttamista edistävä konferenssi järjestettiin Inarissa 7.-9.9.2011. Konferenssissa käsiteltiin maisemasopimuksen tavoitteita, tarpeita ja mahdollisuuksia Pohjois-Kalotin alueella. Tähän raporttiin on koottu konferenssissa esiintyneiden asiantuntijoiden laatimat artikkelit aiheesta. Raportin toivotaan helpottavan alueiden käytön suunnittelijoita käytännön työssään ja rohkaisevan kuntia toteuttamaan tulevaisuuden suunnittelua Eurooppalaisen maisemayleissopimuksen tavoitteiden mukaisesti. Raportti on saatavissa viidellä eri kielellä: suomeksi, ruotsiksi, norjaksi, pohjoissaameksi ja englanniksi. Pohjois-Kalotin aluetta yhdistää yhteinen tunnusomainen maisema. Saamelaiskulttuurin sekä poronhoidon muovaamat tunturimaisemat ja upeat jokivarsimaisemat heijastuvat ympäristössä laaja-alaisesti. Alueen maisemalle haasteita tuovat sen moninaiset maankäyttömuodot ja elinkeinot, kuten matkailu, kaivosteollisuus ja energiantuotanto. Arvokkaiden maisemapiirteiden säilyttäminen vaatii erityistä tuntemusta ja tietämystä alueen kunnissa. Maisemansuojelua ja -hoitoa toteutetaan alueiden- ja maankäytön suunnittelun kautta, pääasiallisesti kaavoituksella ja maisemanhoitosuunnitelmilla. Pohjois-Kalotin alueen kunnissa on erilaiset osin toisistaan poikkeavat toimintatavat ja käytännöt maisemanhoidossa. Kuitenkin alueen asukkailla on yhtäläisiä intressejä elinympäristönsä suojeluun ja säilyttämiseen. Maisema nähdään vetovoimatekijänä, jota ei haluta menettää. Lisääntyvät maankäyttötarpeet kunnissa luovat tarpeen entistä moniulotteisemmalle suunnittelulle. Paikallisten tahojen osallistaminen suunnitteluprosesseihin aikaisessa vaiheessa ja monimuotoinen vuorovaikutus, niin toimijoiden, kansalaisten kuin viranomaisten välillä vähentää konfliktien muodostumista. Tutkimustiedon tehokkaampi hyödyntäminen ja valtiorajat ylittävä yhteistyö helpottaa päätöksentekoa ja luo yhteisiä linjoja maisemansuojelutyöhön. Yhteiset kokemukset, käytännöt ja tietotaidon jakaminen sekä laajemman maisemakokonaisuuden hahmottaminen parantaa eurooppalaisen maisemayleissopimuksen tavoitteiden toteutumista. Työn jatkuvuuden varmistamiseksi Pohjois-Kalotin alueelle suunnitellaan perustettavaksi maisemayhteistyöryhmä, jonka tehtävä on maisemapolitiikan kehittäminen ja eteenpäin vieminen.

Nordliga landskap : "Tillämpning av den europeiska landskapskonventionen i kommunerna på Nordkalotten" - Konferensen 7.-9.9.2011, Enare, Finland

För att kunna nå de uppsatta målen för den europeiska landskapskonventionen anordnades en internationell europeisk konferens den 7–9 september 2011 i Enare. Konferensen var främst inriktad på att öka kunskapen om den europeiska landskapskonventionen och de möjligheter och behov den ger vad gäller det praktiska planeringsarbetet, särkilt på kommunnivå. Den här rapport är samlat artikel skrev av ledande expertes som var föreläsare i konferensen. Vi hoppas att den här rapport underlättar det praktiska arbetet för planerarna av de här områdena och inspirerar kommunerna att genomföra sina framtidsplaner enligt den europeiska landskapskonventionen. Publikationen finns tillgänglig på fem olika språk: finska, svenska, norska, nordsamiska och engelska. Naturen på Nordkalotten återspeglar på bred front de gemensamma karaktäristiska dragen, såsom de fantastiska älvlandskapen och de vackra fjälltrakterna formade av samekulturen och renskötseln. Turism, energiproduktion, gruvnäring och utbyggnad av infrastruktur leder till nya och mångfacetterade utmaningar för dem som är ansvariga för områdena. Kommunerna behöver kunskap och stöd för att kunna förverkliga de allt mer komplexa planerna i framtiden, så att de unika och värdefulla särdragen kan bevaras. Landskapsskyddet och -vården genomförs i landskapsområdena via områdesplanering och planering av markanvändning, i huvudsak genom planläggning och utarbetande av landskapsvårdsplaner. Kommunerna i Nordkalotten har egna, delvis olikartade metoder och praxis, på basis av vilka olika processer i anslutning till områdesanvändningen sköts. Kommunerna och kommuninvånarna har ett stort intresse att bevara och skydda den egna livsmiljön och att upprätthålla och öka områdets attraktionskraft. Landskapet ses ju i kommunerna som en av de viktigaste attraktionsfaktorerna som man inte vill förlora. Kommunernas ökade markanvändningsbehov med avseende på bland annat energiproduktionen, gruvindustrin och den växande turistnäringen skapar ett välgrundat behov av en planering med ännu fler dimensioner. Det är viktigt att lokala intressegrupper deltar i planeringen redan i början av processen. Mångsidigt samarbete mellan medborgare, aktörer och myndigheter kan minska eller hindra konflikter. En dialog mellan medborgare, organisationer och myndigheter har en stor inverkan på många projekts effekter på landskapet. Med hjälp av forskning får vi mer information om landskapen, deras betydelse och hur olika markanvändningsmetoder påverkar landskapen. Gemensamma erfarenheter och praktik, uppdelningen av kunnande (know-how) samt uppfattningen av bredare landkapshelheten dörbättrar tilsammans de möjligheterna att förverkliga målen som definierats i Europeiska landskapkonventionen.För att säkerställa att arbetet fortsätter upprättas en landskapssamarbetsgrupp på Nordkalottens område, som huvuduppgift är att utveckla landskapspolitiken och driva den framåt.

Production of Mg(OH)2 from Mg-silicate rock for CO2 mineral sequestration

Sequestration of carbon dioxide in mineral rocks, also known as CO2 Capture and Mineralization (CCM), is considered to have a huge potential in stabilizing anthropogenic CO2 emissions. One of the CCM routes is the ex situ indirect gas/sold carbonation of reactive materials, such as Mg(OH)2, produced from abundantly available Mg-silicate rocks. The gas/solid carbonation method is intensively researched at Åbo Akademi University (ÅAU ), Finland because it is energetically attractive and utilizes the exothermic chemistry of Mg(OH)2 carbonation. In this thesis, a method for producing Mg(OH)2 from Mg-silicate rocks for CCM was investigated, and the process efficiency, energy and environmental impact assessed. The Mg(OH)2 process studied here was first proposed in 2008 in a Master’s Thesis by the author. At that time the process was applied to only one Mg-silicate rock (Finnish serpentinite from the Hitura nickel mine site of Finn Nickel) and the optimum process conversions, energy and environmental performance were not known. Producing Mg(OH)2 from Mg-silicate rocks involves a two-staged process of Mg extraction and Mg(OH)2 precipitation. The first stage extracts Mg and other cations by reacting pulverized serpentinite or olivine rocks with ammonium sulfate (AS) salt at 400 - 550 oC (preferably < 450 oC). In the second stage, ammonia solution reacts with the cations (extracted from the first stage after they are leached in water) to form mainly FeOOH, high purity Mg(OH)2 and aqueous (dissolved) AS. The Mg(OH)2 process described here is closed loop in nature; gaseous ammonia and water vapour are produced from the extraction stage, recovered and used as reagent for the precipitation stage. The AS reagent is thereafter recovered after the precipitation stage. The Mg extraction stage, being the conversion-determining and the most energy-intensive step of the entire CCM process chain, received a prominent attention in this study. The extraction behavior and reactivity of different rocks types (serpentinite and olivine rocks) from different locations worldwide (Australia, Finland, Lithuania, Norway and Portugal) was tested. Also, parametric evaluation was carried out to determine the optimal reaction temperature, time and chemical reagent (AS). Effects of reactor types and configuration, mixing and scale-up possibilities were also studied. The Mg(OH)2 produced can be used to convert CO2 to thermodynamically stable and environmentally benign magnesium carbonate. Therefore, the process energy and life cycle environmental performance of the ÅAU CCM technique that first produces Mg(OH)2 and the carbonates in a pressurized fluidized bed (FB) were assessed. The life cycle energy and environmental assessment approach applied in this thesis is motivated by the fact that the CCM technology should in itself offer a solution to what is both an energy and environmental problem. Results obtained in this study show that different Mg-silicate rocks react differently; olivine rocks being far less reactive than serpentinite rocks. In summary, the reactivity of Mg-silicate rocks is a function of both the chemical and physical properties of rocks. Reaction temperature and time remain important parameters to consider in process design and operation. Heat transfer properties of the reactor determine the temperature at which maximum Mg extraction is obtained. Also, an increase in reaction temperature leads to an increase in the extent of extraction, reaching a maximum yield at different temperatures depending on the reaction time. Process energy requirement for producing Mg(OH)2 from a hypothetical case of an iron-free serpentine rock is 3.62 GJ/t-CO2. This value can increase by 16 - 68% depending on the type of iron compound (FeO, Fe2O3 or Fe3O4) in the mineral. This suggests that the benefit from the potential use of FeOOH as an iron ore feedstock in iron and steelmaking should be determined by considering the energy, cost and emissions associated with the FeOOH by-product. AS recovery through crystallization is the second most energy intensive unit operation after the extraction reaction. However, the choice of mechanical vapor recompression (MVR) over the “simple evaporation” crystallization method has a potential energy savings of 15.2 GJ/t-CO2 (84 % savings). Integrating the Mg(OH)2 production method and the gas/solid carbonation process could provide up to an 25% energy offset to the CCM process energy requirements. Life cycle inventory assessment (LCIA) results show that for every ton of CO2 mineralized, the ÅAU CCM process avoids 430 - 480 kg CO2. The Mg(OH)2 process studied in this thesis has many promising features. Even at the current high energy and environmental burden, producing Mg(OH)2 from Mg-silicates can play a significant role in advancing CCM processes. However, dedicated future research and development (R&D) have potential to significantly improve the Mg(OH)2 process performance.

Determination of chlorophenols from water by solid phase microextraction - ion mobility spectrometry (SPME-IMS)

Chlorophenols have been classified as possible carcinogens for humans. Chlorophenols have been used as pesticides and wood preservatives. In Finland, during 1930 – 1980s, saw mills used KY-5 wood preservative that contained 2,4,6-TCP, 2,3,4,6-TeCP and PCP. Especially in Finland chlorophenols have entered the environment by leaking from contaminated grounds of old saw mills. Although chlorophenol concentrations found in environment do not cause acute concern, long term exposure can increase the risk of cancer. SPME is relatively cheap and simple sampling method, in which the sample extraction and concentration are performed in a single step. Solvents are not required in SPME. IMS is based on the detection of sample ion drift times. Based on the drift times, reduced mobilities are calculated, which are comparable despite the measurement conditions. SPME-IMS coupling has not been used earlier in the determination of chlorophenols from water samples. The scope of this work was to study, if SPME-IMS system is suitable for detecting chloro-phenols from water samples. The aim was to determine the most optimal extraction condi-tions, which were then applied to real water samples. Following detection limits were deter-mined: 2,4,6-TCP: 0.33 mg/l; 2,3,4,6-TeCP: 0.63 mg/l and PCP: 1.63 mg/l. Detection limits were high compared to the highest possible chlorophenol concentration that is allowed in Finnish drinking water, 10 μg/l. Detected concentrations from water sample differed from verified concentrations in the case of 2,3,4,6-TeCP by 4.6 % and in the case of 2,4,6-TCP by 48.4 %. Based on the results it can be said that SPME-IMS setup is suitable for preliminary analysis of mg/l chlorophenol concentrations from water samples.

Uutta tietoa Kainuun soista : Kainuun suoselvitys -projektin tulosraportti

Raportissa esitellään Kainuun suoselvitys -projektin keskeisimpiä tuloksia ja niistä vedettyjä johtopäätöksiä. Vuosina 2010–2012 toteutetun projektin tarkoituksena on ollut parantaa tietopohjaa Kainuun soista, ja sitä kautta luoda edellytyksiä soiden eri käyttömuotojen yhteensovittamiselle ja samalla nostaa esille Kainuun soihin liittyviä mahdollisuuksia. Soiden käyttö nähtiin projektissa laajasti, sisältäen paitsi erilaiset taloudellisen hyödyntämisen muodot myös soiden merkityksen ihmisten virkistykselle ja hyvinvoinnille sekä luonnon monimuotoisuudelle ja monille sääteleville toiminnoille. Taustana projektille on samaan aikaan laadittu kansallinen suostrategia. Sen mukaan soiden luonnontilaa muuttavien toimintojen, maa-, metsä- ja turvetalouden, tulisi jatkossa toimia jo ojitetuilla tai muuten merkittävästi muuttuneilla soilla. Näin soiden luonnontilaisuudesta hyötyville soiden käytön muodoille ja ekosysteemipalveluille jää paremmin tilaa toimia. Kainuu on Suomen kolmanneksi soisin maakunta. Suot ovat keskeinen osa sen luontoa ja maisemaa ja myös monipuolinen luonnonvara. Valtaosa Kainuun suopinta-alasta on ojitettu. Uutta tietoa on projektissa tuotettu paikkatietomenetelmin ja kohdennetuin maastoselvityksin. Raportin aihepiirejä ovat Kainuun soiden käyttö, jäljellä olevat ojittamattomat suot, suojeltujen soiden vesitaloudellinen eheys, metsätalouden käytöstä poistuvat ojitetut suot, soiden merkitys virkistyksen ja matkailun kannalta sekä maastossa tutkittujen 143 suon arviointi turpeennoston ja luonnon monimuotoisuuden kannalta. Raportissa esitetään, että kansallisen suostrategian tavoite soiden kestävästä ja vastuullisesta käytöstä ja suojelusta on mahdollista saavuttaa eri toimijoiden yhteistyön ja maankäytön ohjauksen avulla. Se edellyttää sitoutumista suostrategian linjauksiin sekä tietopohjan parantamista soista ja eri toimintojen vaikutuksista. Kainuun suoselvitys -projektissa on osaltaan tuotettu tätä tietoa ja myös kehitelty menetelmiä sen hankkimiseksi.

Ion mobility spectrometry in liquid analysis

Ion mobility spectrometry (IMS) is a straightforward, low cost method for fast and sensitive determination of organic and inorganic analytes. Originally this portable technique was applied to the determination of gas phase compounds in security and military use. Nowadays, IMS has received increasing attention in environmental and biological analysis, and in food quality determination. This thesis consists of literature review of suitable sample preparation and introduction methods for liquid matrices applicable to IMS from its early development stages to date. Thermal desorption, solid phase microextraction (SPME) and membrane extraction were examined in experimental investigations of hazardous aquatic pollutants and potential pollutants. Also the effect of different natural waters on the extraction efficiency was studied, and the utilised IMS data processing methods are discussed. Parameters such as extraction and desorption temperatures, extraction time, SPME fibre depth, SPME fibre type and salt addition were examined for the studied sample preparation and introduction methods. The observed critical parameters were extracting material and temperature. The extraction methods showed time and cost effectiveness because sampling could be performed in single step procedures and from different natural water matrices within a few minutes. Based on these experimental and theoretical studies, the most suitable method to test in the automated monitoring system is membrane extraction. In future an IMS based early warning system for monitoring water pollutants could ensure the safe supply of drinking water. IMS can also be utilised for monitoring natural waters in cases of environmental leakage or chemical accidents. When combined with sophisticated sample introduction methods, IMS possesses the potential for both on-line and on-site identification of analytes in different water matrices.

GIS in Digital Repositories

Workshop at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

Segmentation of overlapping convex objects

This thesis presents a framework for segmentation of clustered overlapping convex objects. The proposed approach is based on a three-step framework in which the tasks of seed point extraction, contour evidence extraction, and contour estimation are addressed. The state-of-art techniques for each step were studied and evaluated using synthetic and real microscopic image data. According to obtained evaluation results, a method combining the best performers in each step was presented. In the proposed method, Fast Radial Symmetry transform, edge-to-marker association algorithm and ellipse fitting are employed for seed point extraction, contour evidence extraction and contour estimation respectively. Using synthetic and real image data, the proposed method was evaluated and compared with two competing methods and the results showed a promising improvement over the competing methods, with high segmentation and size distribution estimation accuracy.

Utilization of steelmaking waste materials for production of calcium carbonate (CaCO3)

The steel industry produces, besides steel, also solid mineral by-products or slags, while it emits large quantities of carbon dioxide (CO2). Slags consist of various silicates and oxides which are formed in chemical reactions between the iron ore and the fluxing agents during the high temperature processing at the steel plant. Currently, these materials are recycled in the ironmaking processes, used as aggregates in construction, or landfilled as waste. The utilization rate of the steel slags can be increased by selectively extracting components from the mineral matrix. As an example, aqueous solutions of ammonium salts such as ammonium acetate, chloride and nitrate extract calcium quite selectively already at ambient temperature and pressure conditions. After the residual solids have been separated from the solution, calcium carbonate can be precipitated by feeding a CO2 flow through the solution. Precipitated calcium carbonate (PCC) is used in different applications as a filler material. Its largest consumer is the papermaking industry, which utilizes PCC because it enhances the optical properties of paper at a relatively low cost. Traditionally, PCC is manufactured from limestone, which is first calcined to calcium oxide, then slaked with water to calcium hydroxide and finally carbonated to PCC. This process emits large amounts of CO2, mainly because of the energy-intensive calcination step. This thesis presents research work on the scale-up of the above-mentioned ammonium salt based calcium extraction and carbonation method, named Slag2PCC. Extending the scope of the earlier studies, it is now shown that the parameters which mainly affect the calcium utilization efficiency are the solid-to-liquid ratio of steel slag and the ammonium salt solvent solution during extraction, the mean diameter of the slag particles, and the slag composition, especially the fractions of total calcium, silicon, vanadium and iron as well as the fraction of free calcium oxide. Regarding extraction kinetics, slag particle size, solid-to-liquid ratio and molar concentration of the solvent solution have the largest effect on the reaction rate. Solvent solution concentrations above 1 mol/L NH4Cl cause leaching of other elements besides calcium. Some of these such as iron and manganese result in solution coloring, which can be disadvantageous for the quality of the PCC product. Based on chemical composition analysis of the produced PCC samples, however, the product quality is mainly similar as in commercial products. Increasing the novelty of the work, other important parameters related to assessment of the PCC quality, such as particle size distribution and crystal morphology are studied as well. As in traditional PCC precipitation process, the ratio of calcium and carbonate ions controls the particle shape; a higher value for [Ca2+]/[CO32-] prefers precipitation of calcite polymorph, while vaterite forms when carbon species are present in excess. The third main polymorph, aragonite, is only formed at elevated temperatures, above 40-50 °C. In general, longer precipitation times cause transformation of vaterite to calcite or aragonite, but also result in particle agglomeration. The chemical equilibrium of ammonium and calcium ions and dissolved ammonia controlling the solution pH affects the particle sizes, too. Initial pH of 12-13 during the carbonation favors nonagglomerated particles with a diameter of 1 μm and smaller, while pH values of 9-10 generate more agglomerates of 10-20 μm. As a part of the research work, these findings are implemented in demonstrationscale experimental process setups. For the first time, the Slag2PCC technology is tested in scale of ~70 liters instead of laboratory scale only. Additionally, design of a setup of several hundreds of liters is discussed. For these purposes various process units such as inclined settlers and filters for solids separation, pumps and stirrers for material transfer and mixing as well as gas feeding equipment are dimensioned and developed. Overall emissions reduction of the current industrial processes and good product quality as the main targets, based on the performed partial life cycle assessment (LCA), it is most beneficial to utilize low concentration ammonium salt solutions for the Slag2PCC process. In this manner the post-treatment of the products does not require extensive use of washing and drying equipment, otherwise increasing the CO2 emissions of the process. The low solvent concentration Slag2PCC process causes negative CO2 emissions; thus, it can be seen as a carbon capture and utilization (CCU) method, which actually reduces the anthropogenic CO2 emissions compared to the alternative of not using the technology. Even if the amount of steel slag is too small for any substantial mitigation of global warming, the process can have both financial and environmental significance for individual steel manufacturers as a means to reduce the amounts of emitted CO2 and landfilled steel slag. Alternatively, it is possible to introduce the carbon dioxide directly into the mixture of steel slag and ammonium salt solution. The process would generate a 60-75% pure calcium carbonate mixture, the remaining 25-40% consisting of the residual steel slag. This calcium-rich material could be re-used in ironmaking as a fluxing agent instead of natural limestone. Even though this process option would require less process equipment compared to the Slag2PCC process, it still needs further studies regarding the practical usefulness of the products. Nevertheless, compared to several other CO2 emission reduction methods studied around the world, the within this thesis developed and studied processes have the advantage of existing markets for the produced materials, thus giving also a financial incentive for applying the technology in practice.

Chemical derivatization of galactoglucomannan for functional materials

In the framework of the biorefinery concept researchers aspire to optimize the utilization of plant materials, such as agricultural wastes and wood. For most of the known processes, the first steps in the valorisation of biomass are the extraction and purification of the individual components. The obtained raw products by means of a controlled separation can consecutively be modified to result in biofuels or biogas for energy production, but also in value-added products such as additives and important building blocks for the chemical and material industries. Considerable efforts are undertaken in order to substitute the use of oil-based starting materials or at least minimize their processing for the production of everyday goods. Wood is one of the raw materials, which have gained large attention in the last decades and its composition has been studied in detail. Nowadays, the extraction of water-soluble hemicelluloses from wood is well known and so for example xylan can be obtained from hardwoods and O-acetyl galactoglucomannans (GGMs) from softwoods. The aim of this work was to develop water-soluble amphiphilic materials of GGM and to assess their potential use as additives. Furthermore, GGM was also applied as a crosslinker in the synthesis of functional hydrogels for the removal of toxic metals and metalloid ions from aqueous solutions. The distinguished products were obtained by several chemical approaches and analysed by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FTIR), size exclusion chromatography (SEC), thermal gravimetric analysis (TGA), scanning electron microscope SEM, among others. Bio-based surfactants were produced by applying GGM and different fatty acids as starting materials. On one hand, GGM-grafted-fatty acids were prepared by esterification and on the other hand, well-defined GGM-block-fatty acid derivatives were obtained by linking amino-functional fatty acids to the reducing end of GGM. The reaction conditions for the syntheses were optimized and the resultant amphiphilic GGM derivatives were evaluated concerning their ability to reduce the surface tension of water as surfactants. Furthermore, the block-structured derivatives were tested in respect to their applicability as additives for the surface modification of cellulosic materials. Besides the GGM surfactants with a bio-based hydrophilic and a bio-based hydrophobic part, also GGM block-structured derivatives with a synthetic hydrophobic tail, consisting of a polydimethylsiloxane chain, were prepared and assessed for the hydrophobization of surface of nanofibrillated cellulose films. In order to generate GGM block-structured derivatives containing a synthetic tail with distinguished physical and chemical properties, as well as a tailored chain length, a controlled polymerization method was used. Therefore, firstly an initiator group was introduced at the reducing end of the GGM and consecutively single electron transfer-living radical polymerization (SET-LRP) was performed by applying three different monomers in individual reactions. For the accomplishment of the synthesis and the analysis of the products, challenges related to the solubility of the reactants had to be overcome. Overall, a synthesis route for the production of GGM block-copolymers bearing different synthetic polymer chains was developed and several derivatives were obtained. Moreover, GGM with different molar masses were, after modification, used as a crosslinker in the synthesis of functional hydrogels. Hereby, a cationic monomer was used during the free radical polymerization and the resultant hydrogels were successfully tested for the removal of chromium and arsenic ions from aqueous solutions. The hydrogel synthesis was tailored and materials with distinguished physical properties, such as the swelling rate, were obtained after purification. The results generated in this work underline the potential of bio-based products and the urge to continue carrying out research in order to be able to use more green chemicals for the manufacturing of biorenewable and biodegradable daily products.

Effects of the partial removal of wood hemicelluloses on the properties of kraft pulp

The objective of this work was to study the effects of partial removal of wood hemicelluloses on the properties of kraft pulp.The work was conducted by extracting hemicelluloses (1) by a softwood chip pretreatment process prior to kraft pulping, (2) by alkaline extraction from bleached birch kraft pulp, and (3) by enzymatic treatment, xylanase treatment in particular, of bleached birch kraft pulp. The qualitative and quantitative changes in fibers and paper properties were evaluated. In addition, the applicability of the extraction concepts and hemicellulose-extracted birch kraft pulp as a raw material in papermaking was evaluated in a pilot-scale papermaking environment. The results showed that each examined hemicellulose extraction method has its characteristic effects on fiber properties, seen as differences in both the physical and chemical nature of the fibers. A prehydrolysis process prior to the kraft pulping process offered reductions in cooking time, bleaching chemical consumption and produced fibers with low hemicellulose content that are more susceptible to mechanically induced damages and dislocations. Softwood chip pretreatment for hemicellulose recovery prior to cooking, whether acidic or alkaline, had an impact on the physical properties of the non-refined and refined pulp. In addition, all the pretreated pulps exhibited slower beating response than the unhydrolyzed reference pulp. Both alkaline extraction and enzymatic (xylanase) treatment of bleached birch kraft pulp fibers indicated very selective hemicellulose removal, particularly xylan removal. Furthermore, these two hemicellulose-extracted birch kraft pulps were utilized in a pilot-scale papermaking environment in order to evaluate the upscalability of the extraction concepts. Investigations made using pilot paper machine trials revealed that some amount of alkalineextracted birch kraft pulp, with a 24.9% reduction in the total amount of xylan, could be used in the papermaking stock as a mixture with non-extracted pulp when producing 75 g/m2 paper. For xylanase-treated fibers there were no reductions in the mechanical properties of the 180 g/m2 paper produced compared to paper made from the control pulp, although there was a 14.2% reduction in the total amount of xylan in the xylanase-treated pulp compared to the control birch kraft pulp. This work emphasized the importance of the hemicellulose extraction method in providing new solutions to create functional fibers and in providing a valuable hemicellulose co-product stream. The hemicellulose removal concept therefore plays an important role in the integrated forest biorefinery scenario, where the target is to the co-production of hemicellulose-extracted pulp and hemicellulose-based chemicals or fuels.