Browsing by Author "Jaatinen, Salla"
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Item Biovedyn lähteet(2011) Jaatinen, Salla; Linnekoski, Juha; Kemian tekniikan korkeakoulu; Linnekoski, JuhaItem Carbon Catalysts in Biofuel Production: from Furfural to 2-Methylfuran(Aalto University, 2019) Jaatinen, Salla; Karinen, Reetta, Dr., Aalto University, Department of Chemical and Metallurgical Engineering, Finland; Lehtonen, Juha, Prof., VTT Technical Research Centre of Finland, Finland; Kemian tekniikan ja metallurgian laitos; Department of Chemical and Metallurgical Engineering; Catalysis Research Group; Kemian tekniikan korkeakoulu; School of Chemical Technology; Puurunen, Riikka, Prof., Aalto University, Department of Chemical and Metallurgical Engineering, FinlandProduction of bio-based chemicals, fuels and energy are essential in the current climate environment. Hydrotreatment of renewable platform chemical furfural yields many valuable products, such as furfuryl alcohol and 2-methylfuran (MF). MF has excellent properties for use as a gasoline octane booster to replace current fossil methyl tert-butyl ether and ethyl tert-butyl ether. The current CuCr-catalyst in furfural hydrotreatment is toxic and new and selective catalysts are required. In this dissertation, noble metal free and non-toxic catalysts were prepared for production of MF. Metal catalyst options chosen for this work were copper, nickel and iron. High yields (up to 60%) of MF were achieved with the prepared catalysts in liquid phase batch reactor experiments in short reaction time (1 - 2 h). High temperature (230 °C) and high hydrogen partial pressure (40 bar) were optimal for MF produc-tion, and the most optimal metal combinations were copper-nickel and copper-iron. Active metals were tested in MF production on various activated carbon supports and a mesoporous carbon material (CMK-3). Deep characterization was performed to obtain data of beneficial catalyst characteristics for MF production. Production of MF was enhanced by small metal particle size, small pore volume and higher acidity. These enhancements suppressed the production of competitive products and side reactions, and increased the selectivity towards 2-methylfuran. Solvents may also react in furfural hydrotreatment. The applied 2-propanol can react through catalytic transfer hydrogenation (CTH) offering hydrogen for hydrotreatment reactions and producing acetone. The solvent can also dehydrogenate to acetone and hydrogen. Acetone formation mechanisms were studied with the prepared catalysts. The acetone formation was metal dependent: with nickel and copper acetone formation occurred through CTH while with iron also dehydrogenation took place. Hydrogen solubility in the reaction media is important for the process and especially in scaling up pro-cesses. Hydrogen solubilities in furfural and 2-propanol were measured and observed to increase as a function of temperature (50 - 200 °C) and pressure (50 - 125 bar). Hydrogen solubility in 2-propanol was observed almost three times higher to solubility in furfural. By way of example, at 200 °C and 125 bar hydrogen mole fraction in 2-propanol and furfural was measured to be 0.064 and 0.038 respectively. The solubility data was modelled with PC-SAFT model and the model predicted the hydrogen solubility data well. This dissertation offers a MF selectivity optimized and fast noble metal free catalyst alternative for the current catalyst, new data of hydrogen solubility in the reaction media and optimized carbon support characteristics for the production of MF.Item Furfural Hydrotreatment Applying Isopropanol as a Solvent(SPRINGER/PLENUM PUBLISHERS, 2017-11-01) Jaatinen, Salla; Karinen, Reetta; Department of Chemical and Metallurgical EngineeringIn this study, acetone formation was investigated as a side reaction in furfural hydrotreatment applying isopropanol as a solvent. Acetone formation was observed to depend strongly on the metal and metal loading of catalysts as copper, nickel, and iron catalysts supported on activated carbon were studied. Furfural has an important role in acetone formation: the initial formation rate for acetone was high as long as furfural reacted further. After furfural was consumed the acetone formation decelerated except with the catalysts including iron. Two formation mechanisms were derived: first mechanism includes direct and transfer hydrogenation of furfural and isopropanol dehydrogenation, as mechanism two consists only of isopropanol dehydrogenation. Another novel discovery of the study was the confirmation of the formation mechanism for 2-methylfuran through transfer hydrogenation of furfuryl alcohol in the experiments. In conclusion, the acetone formation as a side product was observed significant and could not be totally prevented.Item Hiilet sokerien dehydratoinnissa ja furfuraalien jatkoreaktioissa(2014-04-08) Jaatinen, Salla; Sairanen, Emma; Karinen, Reetta; Kemian tekniikan korkeakoulu; Lehtonen, JuhaUusiutuvasta raaka-aineesta valmistettu furfuraali on tärkeä kemikaali, joka voi toimia tärkeänä raaka-aineena monille kemikaaleille. Furfuraalin valmistus tapahtuu lignoselluloosan hydrolysoinnilla ja tuotettujen sokerien dehydratoinnilla. Tällä hetkellä furfuraalia tuotetaan homogeenisten happokatalyyttien avulla. Homogeenisten katalyyttien huonoja puolia on kuitenkin korroosio ja katalyytin vaikea erottaminen reaktioliuoksesta. Heterogeeniset katalyytit ovat parempi vaihtoehto sokerien dehydratointiin. Heterogeenisista katalyyteista hiilikatalyytit ovat lupaava vaihtoehto. Hiilikatalyyttien erinomaisuus dehydratointireaktiossa perustuu niiden edullisuuteen, hyvään termiseen kestävyyteen sekä niiden aktiivisuuteen myös vesiliuoksissa. Diplomityön kirjallisuusosassa käsiteltiin myös tärkeiden kemikaalien, furfuraalin ja hydroksimetyylifurfuraalin, jatkojalostamista tarpeellisiksi kemikaaleiksi ja polttoaineiksi. Tämän diplomityön kokeellisessa osassa vertailtiin erilaisten hiilikatalyyttien aktiivisuutta ksyloosin dehydratoinnissa furfuraaliksi. Kokeet suoritettiin panoskokeina 200 °C lämpötilassa, kolmen tunnin reaktioajalla ja veden toimiessa liuottimena. Testattuja hiilikatalyyttivaihtoehtoja olivat kolme erilaista aktiivihiilikatalyyttiä, Sibunit, moniseinäiset hiilinanoputket ja grafeenioksidi. Katalyyttikokeita vertailtiin termisiin kokeisiin. Katalyyttien karakterisointiin käytettiin lämpötilaohjelmoitua desorptiota (temperature programmed desorption, TPD) sekä happo-emäs titrausta. TPD:llä analysoitiin vain aktiivihiilikatalyytit, titraus suoritettiin kaikille katalyyteille. Katalyyttisten reaktioiden saavuttamissa sokerien konversioissa, selektiivisyyksissä furfuraaliksi ja furfuraalin saannoissa ei ollut termisiin kokeisiin verrattuna suuria eroja ksyloosin dehydratointikokeissa. Selvästi vähemmän aktiivinen katalyytti oli moniseinäinen hiilinanoputki. Termisten kokeiden saannot liikkuivat välillä 45,8 - 47,8 %. Parhaimmaksi hiilikatalyytiksi valikoitui Norit RX 3 saavuttaen 48,4 % furfuraalin saannon. Katalyyttien aktivoimiseksi moniseinäisiä hiilinanoputkia ja aktiivihiiltä Norit RB 4 C sulfonoitiin. Sulfonoinnin tulisi lisätä katalyytin pinnalle happoryhmiä, jotka toimivat aktiivisina ryhminä sokereiden dehydratoinnissa. Moniseinäisillä hiilinanoputkilla selektiivisyyden furfuraaliksi havaittiin olevan korkeampi sulfonoidulla katalyytillä. Norit RB 4 C:llä aktiivisuuden nousua ei voitu toistettavasti todistaa. Norit RB 4 C:n toistokokeissa katalyytin selektiivisyys oli selvästi alhaisempi tai sama kuin sulfonoidulla Norit RB 4 C:llä. Aktiivihiilikatalyytit karakterisoitiin lämpötilaohjelmoidulla desorptiolla. Muita katalyyttejä ei analysoitu liian pienen partikkelikoon tai huonon termisen kestävyyden takia. TPD-analyyseissä havaittiin eroja aktiivihiilien sekä käsittelemättömän ja sulfonoidun Norit RB 4 C:n välillä. Käsittelemätön Norit RB 4 C sisälsi eniten happamiksi ryhmiksi esitettyjä hiilidioksidina desorboituvia ryhmiä. Rikkipitoisten ryhmien määrää ei voitu tarkasti määrittää, mutta sulfonoidulla Norit RB 4 C:llä rikkimonoksidin ja rikkidioksidin piikkien intensiteetit olivat suurimmat. Kaikille katalyyteille suoritettiin myös happo-emäs titraus, jolla selvitettiin happamien ryhmien konsentraatio katalyytin pinnalla. Vähiten happamia ryhmiä pinnallaan sisälsi Sibunit, grafeenioksidin ollessa happopaikkojen konsentraation mukaan paras katalyyttivaihtoehto. Moniseinäisten hiilinanoputkien sulfonointi ei lisännyt happamien ryhmien konsentraatiota, Norit RB 4 C:llä se lähes kolminkertaisti happamien ryhmien konsentraation.Item Hiilikatalyyttien karakterisointi(2015-12-07) Lehti, Kia; Jaatinen, Salla; Kemiantekniikan korkeakoulu; Fabricius, GunillaItem Hydrogen solubility in furfural and 2-propanol: Experiments and modeling(ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD, 2017-09-01) Jaatinen, Salla; Touronen, Jouni; Karinen, Reetta; Uusi-Kyyny, Petri; Alopaeus, Ville; Department of Chemical and Metallurgical Engineering; Department of Biotechnology and Chemical Technology; Industrial chemistry; Chemical engineeringProduction of valuable chemicals from furfural through hydrotreatment requires information of hydrogen solubility in furfural and the most often applied solvent, 2-propanol. This study investigates hydrogen solubility in furfural and 2-propanol at the temperature range of 323–476 K and pressure range up to 12.5 MPa. The measured data are compared to prediction with Soave-Redlich-Kwong, Peng-Robinson, and Perturbed-Chain Statistically Associating Fluid Theory (PC-SAFT) equations of state. The most accurate prediction of hydrogen solubility in furfural and 2-propanol was obtained with PC-SAFT.Item Hydrotreatment of furfural to 2-methylfuran with carbon catalysts(2015-06-11) Castellazzi, Sara; Jaatinen, Salla; Karinen, Reetta; Kemian tekniikan korkeakoulu; Lehtonen, Juha2-methylfuran (2-MF) production through liquid-phase catalytic hydrogenation of furfural using 2-propanol as solvent was investigated over carbon-supported catalysts in a batch reactor. Acceptable values of 2-MF yields and selectivity were achieved using impregnated catalysts supported over activated carbon Norit® RB4C. The best results were observed using 2%/2% CuFe catalysts after 5 hours reaction time at 230°C: 42.75% yield and 42.82% selectivity. Nevertheless, with some nickel-based catalysts, such as 2% and 10% Ni, almost 33% and 41% yields of 2-MF were achieved, respectively. An important outcome was that copper catalysts, historically the best catalysts suitable for 2-MF production, showed better results when used in combination with other metals, such as Fe or Ni. Moreover, it is advisable to reduce Cu at lower temperature ( 200°C) in order to improve catalytic performances. Other types of support (i.e. acid-washed Norit® RX3) and preparation techniques (i.e. atomic layer deposition) were tested showing poor results.Item Metallikatalyyttien valmistus impregnoimalla(2015-04-28) Rinta-Paavola, Aleksi; Jaatinen, Salla; Kemiantekniikan korkeakoulu; Fabricius, GunillaItem Study of Ni, Pt, and Ru Catalysts on Wood-based Activated Carbon Supports and their Activity in Furfural Conversion to 2-Methylfuran(Wiley - VCH Verlag GmbH & CO. KGaA, 2018) Mäkelä, Eveliina; Lahti, Riikka; Jaatinen, Salla; Romar, Henrik; Hu, Tao; Puurunen, Riikka L.; Lassi, Ulla; Karinen, Reetta; Department of Chemical and Metallurgical Engineering; Industrial chemistry; Catalysis; University of Oulu; Kokkola University Consortium ChydeniusBio-based chemicals can be produced from furfural through hydrotreatment. In this study, 2-methylfuran (MF), a potential biofuel component, was produced with Pt, Ru, and Ni catalysts supported on wood-based activated carbons. The catalytic hydrotreatment experiments were conducted in a batch reactor at 210-240°C with 2-propanol as solvent and 40bar H2 pressure. Two types of activated carbon supports were prepared by carbonization and activation of lignocellulosic biomass (forest-residue-based birch and spruce from Finland). Both types of activated carbons were suitable as catalyst supports, giving up to 100% furfural conversions. The most important factors affecting the MF yield were the metal dispersion and particle size as well as reaction temperature. The highest observed MF yields were achieved with the noble metal catalysts with the highest dispersions at 240°C after 120min reaction time: 3wt% Pt on spruce (MF yield of 50%) and 3wt% Ru on birch (MF yield of 49%). Nickel catalysts were less active most likely owing to lower dispersions and incomplete metal reduction. Interesting results were obtained also with varying the metal loadings: the lower Pt loading (1.5wt%) achieved almost the same MF yield as the 3wt% catalysts, which can enable the production of MF with high yields and reduced catalyst costs. Based on this study, biomass-based renewable activated carbons can be used as catalyst supports in furfural hydrotreatment with high conversions.
