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Regulatory Intermediaries and Chains – the Complex Process of Sensemaking for AI Act Implementation in Finland
No full textAbstract
The European Union (EU) Artificial Intelligence (AI) Act entered into force in August 2024. It aims to address different risks involved with AI systems. The regulation not only concerns organizations providing or deploying AI systems, but it mandates EU Member States to comply with the AI Act and change national law, if necessary. Member States act in the role of a regulatory intermediary (RI) for the AI Act. We conducted an interpretive case study to understand how a working group tasked with Finland’s national-level AI Act implementation made sense of changes the AI Act required to the national law for designation of National Competent Authorities. We contribute to Information Systems research by shedding light on the institutional process leading to new national law, highlighting Member States' role as an RI in implementing the AI Act on a national-level and introducing the concept of a regulatory chain involving multiple RIs.Abstract
The European Union (EU) Artificial Intelligence (AI) Act entered into force in August 2024. It aims to address different risks involved with AI systems. The regulation not only concerns organizations providing or deploying AI systems, but it mandates EU Member States to comply with the AI Act and change national law, if necessary. Member States act in the role of a regulatory intermediary (RI) for the AI Act. We conducted an interpretive case study to understand how a working group tasked with Finland’s national-level AI Act implementation made sense of changes the AI Act required to the national law for designation of National Competent Authorities. We contribute to Information Systems research by shedding light on the institutional process leading to new national law, highlighting Member States' role as an RI in implementing the AI Act on a national-level and introducing the concept of a regulatory chain involving multiple RIs
Predicting optimal impact interventions in the post-HPV vaccination world
No full textAbstract
Prophylactic vaccination is a powerful tool that changes exposure to infections and associated morbidity of preventable diseases. We discuss the impact of pneumococci and human papillomavirus (HPV) vaccination on the population biology of the two micro-organisms and related public health effects. Data on HPV type-replacement in communities where vaccine-covered HPVs are almost eliminated, and interactions of the remaining HPV types on the risk of cervical cancer are reviewed. Results of comprehensive models for European country-specific conduction of cervical screening among HPV-vaccinated and unvaccinated women, assuming different HPV-vaccination coverage and strategies, are discussed in our policy-oriented review. An acceptable balance of benefits and harms of cervical cancer screening in HPV vaccinated populations requires an understanding of cancer risks in differently vaccinated birth cohorts. Finally, the challenges are complex but can be met if strategies are applied that (i) as fast as possible achieve herd effect and (ii) use a risk-based design of HPV screening.Abstract
Prophylactic vaccination is a powerful tool that changes exposure to infections and associated morbidity of preventable diseases. We discuss the impact of pneumococci and human papillomavirus (HPV) vaccination on the population biology of the two micro-organisms and related public health effects. Data on HPV type-replacement in communities where vaccine-covered HPVs are almost eliminated, and interactions of the remaining HPV types on the risk of cervical cancer are reviewed. Results of comprehensive models for European country-specific conduction of cervical screening among HPV-vaccinated and unvaccinated women, assuming different HPV-vaccination coverage and strategies, are discussed in our policy-oriented review. An acceptable balance of benefits and harms of cervical cancer screening in HPV vaccinated populations requires an understanding of cancer risks in differently vaccinated birth cohorts. Finally, the challenges are complex but can be met if strategies are applied that (i) as fast as possible achieve herd effect and (ii) use a risk-based design of HPV screening
Opening pathways to sustainable cultural tourism in the North : a white paper
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1. Background
2. Problem statement
3. Connecting culture, creativity and tourism
4. Managing culture for sustainable growth
5. Regional perspectives on creativity and cultural tourism
6. Implementing culture-led development: European Capital of Culture as a platform for renewal
7. Barriers to collaboration in sustainable cultural and creative tourism
8. Opportunities for sustainable cultural and creative tourism
9. Recommendations
10. ReferencesContents
1. Background
2. Problem statement
3. Connecting culture, creativity and tourism
4. Managing culture for sustainable growth
5. Regional perspectives on creativity and cultural tourism
6. Implementing culture-led development: European Capital of Culture as a platform for renewal
7. Barriers to collaboration in sustainable cultural and creative tourism
8. Opportunities for sustainable cultural and creative tourism
9. Recommendations
10. Reference
Associations between the brain glymphatic system and mitochondrial (dys)function: a systematic review
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Introduction:
Previous studies have shown that the proper functioning of both mitochondria and the glymphatic system transporting metabolites are essential for brain health. The aim of this systematic review was to identify the current evidence-based data regarding the relationship between mitochondria and the glymphatic system.
Methods:
This systematic review was conducted following PRISMA guidelines. The databases of PubMed, Scopus, Medline, and Web of Science were searched on June 11, 2024, for eligible studies published until June 1, 2024.
Results:
Of 103 studies, six were included: two original studies and four review articles. All the included studies consistently indicated that the mitochondria and the glymphatic system are likely interconnected, with evidence suggesting several potential links between them. According to original studies, mitochondrial abnormalities in idiopathic normal pressure hydrocephalus (iNPH) and idiopathic intracranial hypertension (IIH) may disrupt glymphatic system function. The included reviews highlighted REM sleep deprivation, melatonin, and inflammation as potential factors linking mitochondria and the glymphatic system.
Discussion:
The relationship between mitochondria and the glymphatic system is complex. Further research is needed to clarify the precise mechanisms of interaction as the current literature is largely speculative. Existing evidence suggests that mitochondrial abnormalities are present in iNPH and IIH, conditions related to impaired CSF flow and impaired glymphatic function. In addition, sleep and melatonin potentially link mitochondrial activity and the glymphatic system function and thus offer potential avenues to ameliorate disorders associated with glymphatic dysfunction by enhancing mitochondrial activity.Abstract
Introduction:
Previous studies have shown that the proper functioning of both mitochondria and the glymphatic system transporting metabolites are essential for brain health. The aim of this systematic review was to identify the current evidence-based data regarding the relationship between mitochondria and the glymphatic system.
Methods:
This systematic review was conducted following PRISMA guidelines. The databases of PubMed, Scopus, Medline, and Web of Science were searched on June 11, 2024, for eligible studies published until June 1, 2024.
Results:
Of 103 studies, six were included: two original studies and four review articles. All the included studies consistently indicated that the mitochondria and the glymphatic system are likely interconnected, with evidence suggesting several potential links between them. According to original studies, mitochondrial abnormalities in idiopathic normal pressure hydrocephalus (iNPH) and idiopathic intracranial hypertension (IIH) may disrupt glymphatic system function. The included reviews highlighted REM sleep deprivation, melatonin, and inflammation as potential factors linking mitochondria and the glymphatic system.
Discussion:
The relationship between mitochondria and the glymphatic system is complex. Further research is needed to clarify the precise mechanisms of interaction as the current literature is largely speculative. Existing evidence suggests that mitochondrial abnormalities are present in iNPH and IIH, conditions related to impaired CSF flow and impaired glymphatic function. In addition, sleep and melatonin potentially link mitochondrial activity and the glymphatic system function and thus offer potential avenues to ameliorate disorders associated with glymphatic dysfunction by enhancing mitochondrial activity
Cytokine profiling of molecular endotypes of knee osteoarthritis: insights from the IMI-APPROACH cohort
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Background:
Molecular endotypes that decipher the heterogeneity of osteoarthritis (OA) have been described. This exploratory study aimed to further the molecular understanding of three previously identified biomarker-based endotypes of knee OA through cytokine profiling.
Methods:
Fifteen pro- and anti-inflammatory cytokines were measured in serum at the six-, 12-, and 24-month follow-up visits of 277 knee OA participants from IMI-APPROACH using Luminex multiplexed immunoassays. Longitudinal differences in cytokine levels between previously defined endotype subgroups; (i) structural damage to bone and cartilage, (ii) low tissue turnover, and (iii) connective tissue inflammation were estimated with linear mixed-effects models, adjusting for patient-specific random effects, age, sex, and BMI. Within-patient stability of the cytokines over 18 months was compared to 19 tissue turnover biomarkers of which defined the endotypes.
Results:
Compared to tissue-turnover biomarkers measured in IMI-APPROACH, the panel of 15 cytokines demonstrated increased fluctuations over time with lower within-patient stability and less discriminatory abilities between the endotype. Only the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1ra) was consistently and differentially elevated in the inflammatory endotype subgroup (n = 92). At the 12-month visit, a mean change of IL-1ra of 36% (95% CI: 19%, 54%; p-value < 0.001) was found for the inflammatory endotype relative to the structural damage endotype, and 40% (95% CI: 22%, 59%; p-value < 0.001) at month 24. At the 24-month visit, a mean change of IL-1ra of 21% (95% CI: 10%, 31%; p-value = 0.047) was found for the inflammatory endotype relative to the low tissue turnover endotype. Participants with the highest quartile expression of IL-1ra within the inflammatory endotype (n = 23) exhibited higher BMI (p = 0.035, Mann-Whitney U test) and worsened Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function (p = 0.035, Mann-Whitney U test) compared to the lowest quartile of IL-1ra expression.
Conclusions:
This study found that the majority of the cytokines exhibited considerable fluctuations over time with no endotype-specific cytokine profiles. This study indicates that while the included cytokines are important for the understanding of OA pathology, they may not be stable reflections of the endotypic profiles of KOA over time.Abstract
Background:
Molecular endotypes that decipher the heterogeneity of osteoarthritis (OA) have been described. This exploratory study aimed to further the molecular understanding of three previously identified biomarker-based endotypes of knee OA through cytokine profiling.
Methods:
Fifteen pro- and anti-inflammatory cytokines were measured in serum at the six-, 12-, and 24-month follow-up visits of 277 knee OA participants from IMI-APPROACH using Luminex multiplexed immunoassays. Longitudinal differences in cytokine levels between previously defined endotype subgroups; (i) structural damage to bone and cartilage, (ii) low tissue turnover, and (iii) connective tissue inflammation were estimated with linear mixed-effects models, adjusting for patient-specific random effects, age, sex, and BMI. Within-patient stability of the cytokines over 18 months was compared to 19 tissue turnover biomarkers of which defined the endotypes.
Results:
Compared to tissue-turnover biomarkers measured in IMI-APPROACH, the panel of 15 cytokines demonstrated increased fluctuations over time with lower within-patient stability and less discriminatory abilities between the endotype. Only the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1ra) was consistently and differentially elevated in the inflammatory endotype subgroup (n = 92). At the 12-month visit, a mean change of IL-1ra of 36% (95% CI: 19%, 54%; p-value < 0.001) was found for the inflammatory endotype relative to the structural damage endotype, and 40% (95% CI: 22%, 59%; p-value < 0.001) at month 24. At the 24-month visit, a mean change of IL-1ra of 21% (95% CI: 10%, 31%; p-value = 0.047) was found for the inflammatory endotype relative to the low tissue turnover endotype. Participants with the highest quartile expression of IL-1ra within the inflammatory endotype (n = 23) exhibited higher BMI (p = 0.035, Mann-Whitney U test) and worsened Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function (p = 0.035, Mann-Whitney U test) compared to the lowest quartile of IL-1ra expression.
Conclusions:
This study found that the majority of the cytokines exhibited considerable fluctuations over time with no endotype-specific cytokine profiles. This study indicates that while the included cytokines are important for the understanding of OA pathology, they may not be stable reflections of the endotypic profiles of KOA over time
Bibliometric and Content Analysis of Sustainable Education in Biology for Promoting Sustainability at Primary and Secondary Schools and in Teacher Education
No full textAbstract
The integration of sustainable development into biology education has been a growing area of interest. Biology education for sustainability is considered through competencies and skills, taking different dimensions of knowledge into account. Solving problems requires not only knowledge but also communicative and strategic activity. Thus, biology education must emphasize the main visions of scientific literacy proposed in the literature, supporting students to understand society and everyday socioscientific challenges at the local as well as at the global level, and to deal with differing scientific results and uncertain information. However, there are very few studies from a holistic didactic viewpoint on the implementation of sustainable education (SE) in biology education in the context of teacher education and school education for promoting a sustainable future. This study addresses this gap via a bibliometric and content analysis of the literature (n = 165 and 131, respectively) based on the categories of the sustainable development goals (SDGs), subject aims, learning objectives, content knowledge, teaching methods, competencies and skills, and assessment methods. The literature analyzed emphasizes the environmental and social SDGs, the development of students’ factual and conceptual knowledge and learning, interactive teaching and learning methods, critical thinking and reflection, and summative and formative assessment methods. There is much less attention on economic and institutional SDGs, scientific skills, environmental attitudes, knowledge creation, strategic thinking and empathy, and diagnostic assessment methods. Compared to earlier studies performed in the 2010s, teaching and learning methods have become more diverse in contrast to the earlier focus on teacher-centered methods. Overall, the conclusion is that biology education must evolve beyond content mastery to integrate ethical, technological, and transdisciplinary dimensions—empowering learners not only to understand life but to sustain it—aligned with quality education (SDG 4), good health and well-being (SDG 3), and life on land (SDG 15). The findings also suggest that powerful knowledge needs to be emphasized for providing essential insights into ecosystems, biodiversity, and the processes that sustain life on Earth. They also highlight the importance of regular evaluations of teaching and learning for detecting how pedagogical and didactic approaches and strategies have supported students’ learning focused on sustainable development.Abstract
The integration of sustainable development into biology education has been a growing area of interest. Biology education for sustainability is considered through competencies and skills, taking different dimensions of knowledge into account. Solving problems requires not only knowledge but also communicative and strategic activity. Thus, biology education must emphasize the main visions of scientific literacy proposed in the literature, supporting students to understand society and everyday socioscientific challenges at the local as well as at the global level, and to deal with differing scientific results and uncertain information. However, there are very few studies from a holistic didactic viewpoint on the implementation of sustainable education (SE) in biology education in the context of teacher education and school education for promoting a sustainable future. This study addresses this gap via a bibliometric and content analysis of the literature (n = 165 and 131, respectively) based on the categories of the sustainable development goals (SDGs), subject aims, learning objectives, content knowledge, teaching methods, competencies and skills, and assessment methods. The literature analyzed emphasizes the environmental and social SDGs, the development of students’ factual and conceptual knowledge and learning, interactive teaching and learning methods, critical thinking and reflection, and summative and formative assessment methods. There is much less attention on economic and institutional SDGs, scientific skills, environmental attitudes, knowledge creation, strategic thinking and empathy, and diagnostic assessment methods. Compared to earlier studies performed in the 2010s, teaching and learning methods have become more diverse in contrast to the earlier focus on teacher-centered methods. Overall, the conclusion is that biology education must evolve beyond content mastery to integrate ethical, technological, and transdisciplinary dimensions—empowering learners not only to understand life but to sustain it—aligned with quality education (SDG 4), good health and well-being (SDG 3), and life on land (SDG 15). The findings also suggest that powerful knowledge needs to be emphasized for providing essential insights into ecosystems, biodiversity, and the processes that sustain life on Earth. They also highlight the importance of regular evaluations of teaching and learning for detecting how pedagogical and didactic approaches and strategies have supported students’ learning focused on sustainable development
Protecting text classifier models against backdoor attacks
No full textTakaporttihyökkäykset ovat välitön uhka tekoälyn ja yleisesti ottaen uuden teknologian kestävyydelle. Tässä työssä perehdytään luonnollisen kielen käsittelyä (eng. natural language processing, NLP) hyödyntävien luokittelumallien puolustamiseen erilaisia takaporttihyökkäyksiä vastaan. Vertailtavia puolustusmenetelmiä ovat ONION, parafrasointi takaisinkäännöksen avulla (eng. back-translation paraphrasing, BTP) ja STRIP. Sekä ONION että BTP pyrkivät suojaamaan mallia haitallisilta syötteiltä poistamalla niistä sanat, jotka menetelmä luokittelee poikkeaviksi tai haitallisiksi. STRIP keskittyy yksittäisten sanojen sijaan kokonaisten syötteiden torjumiseen luokittelemalla ne ensin haitallisiin ja puhtaisiin. Kutakin menetelmää verrataan keskenään erilaisilla merkki-, sana-, fraasi- ja virkepohjaisilla laukaisimilla myrkytettyjen tietojoukkojen avulla. Koetulokset osoittavat, että STRIP-menetelmä tarjoaa malleille kattavimman suojan hyökkäyksiä vastaan laukaisintyypistä riippumatta
Elokuvan "The Diary of Paulina P." välikäännös ELF:n avulla : autoetnografinen tarkastelu
No full textThis thesis examines the use of English as a lingua franca (ELF) as an intermediary language in the subtitling of The Diary of Paulina P. for the Oulu International Children’s and Youth Film Festival. Using an autoethnographic approach, the study investigates how intermediary translation through ELF shapes the translator’s subjective experience and influences the resulting Finnish subtitles. The analysis focuses on selected subtitle excerpts translated across Croatian, English, and Finnish and explores how meaning is negotiated rather than directly transferred through the intermediary layer. The findings demonstrate that while ELF enables access to the source material in a globalized translation context, it also introduces ambiguity, semantic drift, and shifts in tone and cultural nuance. At the same time, audiovisual context, functional equivalence, and collaboration with festival staff support the translator in resolving uncertainties and producing coherent target texts. By foregrounding the translator’s situated perspective, this thesis highlights intermediary translation as an interpretive, negotiated, and ethical practice, and underscores the need for greater critical awareness of its effects on both translators and translated texts.Tässä tutkielmassa tarkastellaan englannin lingua francana (ELF) käyttöä välikielenä elokuvan The Diary of Paulina P. suomenkielisten tekstitysten laatimisessa Oulun kansainväliselle lasten- ja nuortenelokuvien festivaalille. Autoetnografisen lähestymistavan avulla tutkimus selvittää, miten ELF:n kautta tapahtuva välikäännös muokkaa kääntäjän subjektiivista kokemusta ja vaikuttaa lopullisiin suomenkielisiin tekstityksiin. Analyysi perustuu valikoituihin tekstitysesimerkkeihin kroatian, englannin ja suomen kielten välillä ja tarkastelee, miten merkityksiä neuvotellaan käännösprosessissa sen sijaan, että ne siirtyisivät suoraan kielestä toiseen. Tulokset osoittavat, että ELF mahdollistaa pääsyn lähdetekstiin globalisoituneessa käännöskontekstissa, mutta samalla se lisää monitulkintaisuutta sekä johtaa merkitysten muuntumiseen ja muutoksiin sävyssä ja kulttuurisissa vivahteissa. Audiovisuaalinen konteksti, toiminnallinen vastaavuus ja yhteistyö festivaalin henkilökunnan kanssa tukevat kuitenkin kääntäjää epävarmuuksien ratkaisemisessa ja toimivien kohdetekstien tuottamisessa. Korostamalla kääntäjän tilanteeseen sidottua näkökulmaa tutkielma tarkastelee välikäännöstä tulkitsevana, neuvoteltuna ja eettisesti merkittävänä käytäntönä sekä painottaa tarvetta lisätä kriittistä tietoisuutta sen vaikutuksista sekä kääntäjiin että käännettyihin teksteihin
Inclusive and child supporting physical learning enviroment in early childhood education and care
No full textImproved circularity by manganese upgrading from secondary material flows
No full textAbstract
The rapidly expanding battery market is driving increased demand for battery-grade chemicals, including manganese sulfate and lithium salts. Furthermore, recent EU battery legislation mandates improved recycling efficiencies and mandates that future batteries contain defined proportions of recycled critical elements. Consequently, the importance of secondary raw materials—beyond battery black mass—is expected to increase.
This thesis investigates the recovery of manganese from manganese-rich residues produced by the zinc industry. In sulfate media, manganese was successfully purified from this industrial side stream. The resulting concentrated manganese sulfate solution was further processed, although minor impurities such as potassium, zinc, calcium, and magnesium remained. A combination of washing, sulfide precipitation, and sulfuric acid-assisted crystallization was employed to purify the leachate and produce battery-grade MnSO4·H2O crystals. In addition, NCM811 cathode active materials (CAMs) were precipitated from partially purified manganese solutions and compared with a reference CAM sample.
The second part of the thesis focuses on lithium recovery from various CAMs using a NiSO4 solution under hydrothermal conditions. This method can be integrated with the manganese recovery process by using delithiated CAM as an oxidizing agent for manganese. Delithiation was performed either in situ or prior to acid leaching, and the delithiated CAM was then used to oxidize the manganese. Both approaches achieved lithium recovery yields exceeding 95%. Notably, hydrothermal delithiation offers advantages over acid leaching, as it selectively dissolving lithium and precipitating nickel into the solid residue. Original papers Kauppinen, T., Vielma, T., Salminen, J., & Lassi, U. (2020). Selective recovery of manganese from anode sludge residue by reductive leaching. ChemEngineering, 4(2), 40. https://doi.org/10.3390/chemengineering4020040 https://doi.org/10.3390/chemengineering4020040 Self-archived version Kauppinen, T., Rautio, L., Flores, A.H., Manninen, M., Hu, T., Salminen, J., Vielma, T., & Lassi, U. (2025). Purification of the manganese sulfate solution obtained from manganese sludge using sulfide precipitation and sulfuric acid-assisted crystallization. Manuscript in preparation. Kauppinen, T., Flores, A.H., Laine, T., Vielma, T., Hu, T., Salminen, J., & Lassi, U. (2025). Selective recovery of lithium from cathode active material under hydrothermal conditions. Manuscript in preparation. Kauppinen, T., Vielma, T., Salminen, J., Manninen, Hu, T., & Lassi, U. (in press). Utilization of Nirich NCM cathode material as an oxidation chemical to control manganese in Li-ion battery waste recycling. https://doi.org/10.1016/j.hydromet.2026.106647 https://doi.org/10.1016/j.hydromet.2026.106647 Kauppinen, T., Laine, P., Välikangas, J., Tynjälä, P., Hu, T., Salminen, J., & Lassi, U. (2023). Co‐precipitation of NCM 811 using recycled and purified manganese: Effect of impurities on the battery cell performance. ChemElectroChem, 10(17), e202300265. https://doi.org/10.1002/celc.202300265 https://doi.org/10.1002/celc.202300265 Self-archived version Tiivistelmä
Akkuteollisuuden kasvu lisää akkulaatuisten kemikaalien, kuten mangaanisulfaatin ja litiumsuolojen, kysyntää. EU:n uusi akkudirektiivi edellyttää lisäksi nykyistä korkeampia kierrätystehokkuuksia ja määrittää, että uusiin akkuihin on sisällytettävä määritelty osuus kierrätettyjä raaka-aineita. Tämän seurauksena perinteisen mustamassan ohella myös muiden sekundääristen raaka-aineiden merkityksen odotetaan kasvavan.
Tässä väitöskirjatutkimuksessa keskityttiin mangaanin talteenottoon sinkkiteollisuuden mangaanipitoisesta sivuainevirrasta, josta mangaani erotettiin onnistuneesti sulfaattiliuoksessa. Liuotuksesta saatua väkevää mangaanisulfaattiliuosta oli puhdistettava, koska se sisälsi edelleen pieniä pitoisuuksia epäpuhtauksia, kuten kaliumia, sinkkiä, kalsiumia ja magnesiumia. Liuoksen puhdistukseen käytettiin pesua, sulfidisaostusta ja rikkihappoavusteista kiteytystä, jolloin liuoksesta saatiin erotettua akkulaatuisia MnSO4·H2O kiteitä. Lisäksi NCM811-katodiaktiivimateriaalia valmistettiin osittain puhdistetuista mangaanisulfaattiliuoksista ja verrattiin puhtaasta mangaanisulfaatista valmistettuun referenssimateriaaliin.
Väitöskirjan toisessa osassa litium liuotettiin selektiivisesti katodimateriaaleista hydrotermisissä olosuhteissa nikkelisulfaattiliuosta hyödyntäen. Tämä menetelmä voidaan integroida mangaanin talteenottoprosessiin hyödyntämällä delitioitua katodimateriaalia mangaanin hapettimena. Delitiointi suoritettiin joko in-situ tai etukäteen happoliuotuksella, minkä jälkeen delitioitua katodimateriaalia käytettiin mangaanin hapettamiseen. Molemmissa tavoissa saavutettiin yli 95-prosenttinen litiumin saanto. Hydroterminen delitiointi tarjosi happoliuotukseen verrattuna etuja liuottamalla litiumin selektiivisesti sekä saostamalla nikkeliä liuoksesta kiinteään jäännökseen. Osajulkaisut Kauppinen, T., Vielma, T., Salminen, J., & Lassi, U. (2020). Selective recovery of manganese from anode sludge residue by reductive leaching. ChemEngineering, 4(2), 40. https://doi.org/10.3390/chemengineering4020040 https://doi.org/10.3390/chemengineering4020040 Rinnakkaistallennettu versio Kauppinen, T., Rautio, L., Flores, A.H., Manninen, M., Hu, T., Salminen, J., Vielma, T., & Lassi, U. (2025). Purification of the manganese sulfate solution obtained from manganese sludge using sulfide precipitation and sulfuric acid-assisted crystallization. Manuscript in preparation. Kauppinen, T., Flores, A.H., Laine, T., Vielma, T., Hu, T., Salminen, J., & Lassi, U. (2025). Selective recovery of lithium from cathode active material under hydrothermal conditions. Manuscript in preparation. Kauppinen, T., Vielma, T., Salminen, J., Manninen, Hu, T., & Lassi, U. (in press). Utilization of Nirich NCM cathode material as an oxidation chemical to control manganese in Li-ion battery waste recycling. https://doi.org/10.1016/j.hydromet.2026.106647 https://doi.org/10.1016/j.hydromet.2026.106647 Kauppinen, T., Laine, P., Välikangas, J., Tynjälä, P., Hu, T., Salminen, J., & Lassi, U. (2023). Co‐precipitation of NCM 811 using recycled and purified manganese: Effect of impurities on the battery cell performance. ChemElectroChem, 10(17), e202300265. https://doi.org/10.1002/celc.202300265 https://doi.org/10.1002/celc.202300265 Rinnakkaistallennettu versio Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Technology and Natural Sciences of the University of Oulu for public defence in Ulappa, Kokkolan yliopistokeskus Chydenius, on 20 February 2026, at 12 noonAbstract
The rapidly expanding battery market is driving increased demand for battery-grade chemicals, including manganese sulfate and lithium salts. Furthermore, recent EU battery legislation mandates improved recycling efficiencies and mandates that future batteries contain defined proportions of recycled critical elements. Consequently, the importance of secondary raw materials—beyond battery black mass—is expected to increase.
This thesis investigates the recovery of manganese from manganese-rich residues produced by the zinc industry. In sulfate media, manganese was successfully purified from this industrial side stream. The resulting concentrated manganese sulfate solution was further processed, although minor impurities such as potassium, zinc, calcium, and magnesium remained. A combination of washing, sulfide precipitation, and sulfuric acid-assisted crystallization was employed to purify the leachate and produce battery-grade MnSO4·H2O crystals. In addition, NCM811 cathode active materials (CAMs) were precipitated from partially purified manganese solutions and compared with a reference CAM sample.
The second part of the thesis focuses on lithium recovery from various CAMs using a NiSO4 solution under hydrothermal conditions. This method can be integrated with the manganese recovery process by using delithiated CAM as an oxidizing agent for manganese. Delithiation was performed either in situ or prior to acid leaching, and the delithiated CAM was then used to oxidize the manganese. Both approaches achieved lithium recovery yields exceeding 95%. Notably, hydrothermal delithiation offers advantages over acid leaching, as it selectively dissolving lithium and precipitating nickel into the solid residue.Tiivistelmä
Akkuteollisuuden kasvu lisää akkulaatuisten kemikaalien, kuten mangaanisulfaatin ja litiumsuolojen, kysyntää. EU:n uusi akkudirektiivi edellyttää lisäksi nykyistä korkeampia kierrätystehokkuuksia ja määrittää, että uusiin akkuihin on sisällytettävä määritelty osuus kierrätettyjä raaka-aineita. Tämän seurauksena perinteisen mustamassan ohella myös muiden sekundääristen raaka-aineiden merkityksen odotetaan kasvavan.
Tässä väitöskirjatutkimuksessa keskityttiin mangaanin talteenottoon sinkkiteollisuuden mangaanipitoisesta sivuainevirrasta, josta mangaani erotettiin onnistuneesti sulfaattiliuoksessa. Liuotuksesta saatua väkevää mangaanisulfaattiliuosta oli puhdistettava, koska se sisälsi edelleen pieniä pitoisuuksia epäpuhtauksia, kuten kaliumia, sinkkiä, kalsiumia ja magnesiumia. Liuoksen puhdistukseen käytettiin pesua, sulfidisaostusta ja rikkihappoavusteista kiteytystä, jolloin liuoksesta saatiin erotettua akkulaatuisia MnSO4·H2O kiteitä. Lisäksi NCM811-katodiaktiivimateriaalia valmistettiin osittain puhdistetuista mangaanisulfaattiliuoksista ja verrattiin puhtaasta mangaanisulfaatista valmistettuun referenssimateriaaliin.
Väitöskirjan toisessa osassa litium liuotettiin selektiivisesti katodimateriaaleista hydrotermisissä olosuhteissa nikkelisulfaattiliuosta hyödyntäen. Tämä menetelmä voidaan integroida mangaanin talteenottoprosessiin hyödyntämällä delitioitua katodimateriaalia mangaanin hapettimena. Delitiointi suoritettiin joko in-situ tai etukäteen happoliuotuksella, minkä jälkeen delitioitua katodimateriaalia käytettiin mangaanin hapettamiseen. Molemmissa tavoissa saavutettiin yli 95-prosenttinen litiumin saanto. Hydroterminen delitiointi tarjosi happoliuotukseen verrattuna etuja liuottamalla litiumin selektiivisesti sekä saostamalla nikkeliä liuoksesta kiinteään jäännökseen