Optimization of manganese recovery from a solution based on lithium-ion batteries by solvent extraction with d2ehpa

Manganese is a critical metal for the steelmaking industry, and it is expected that its world demand will be increasingly affected by the growing market of lithium-ion batteries. In addition to the increasing importance of manganese, its recycling is mainly determined by trends in the recycling of iron and steel. The recovery of manganese by solvent extraction has been widely investigated; however, the interaction of different variables affecting the process is generally not assessed. In this study, the solvent extraction of manganese from a solution based on lithium-ion batteries was modeled and optimized using factorial designs of experiments and the response surface methodology. Under optimized conditions (O:A of 1.25:1, pH 3.25, and 0.5 M bis(2-ethylhexyl) phosphoric acid (D2EHPA)), extractions above 70% Mn were reached in a single extraction stage with a coextraction of less than 5% Co, which was mostly removed in two scrubbing stages. A stripping product containing around 23 g/L Mn and around 0.3 g/L Co can be obtained under optimized conditions (O:A of 8:1, 1 M H2SO4 and around 13 min of contact time) in one stripping stage

‘I miss the physical presence of the students’ : Swedish teachers’ experiences of online teaching and learning during the COVID-19 pandemic

Peer reviewedPublisher PD

Digitaliseringens begränsande gränslöshet – om lärande, rum och hemmahörande i högre utbildning

Digitaliserade lärandemiljöer och distansöverbryggande utbildningsformer har under en längre tid präglat högre utbildning, men den drastiska digitala omställningen i samband med covid-19-pandemin innebar en situation där lärare och studenter i än högre utsträckning kom att skiljas åt i tid och rum. Under våren 2021, när studenter och lärare vid universitet och högskolor under drygt ett år hade bedrivit dessa av regering och myndigheter föreskrivna distansstudier och interagerat i och med de digitaliserade utbildningsmiljöerna, inbjöds tre studentgrupper att delge sina erfarenheter av den digitala omställningen. Studiens övergripande syfte var att synliggöra, kritiskt granska och diskutera studenters erfarenheter av den hastiga och genomgripande digitala transformationen av undervisning och lärandemiljö. Sammanlagt deltog 39 studenter, vilka studerade vid två olika universitet: ett i Sverige och ett på Island. Studenterna fick skriftligt reflektera över ett antal öppna frågeställningar i anslutning till den digitala transformation som deras utbildning genomgått med fokus på upplevelser och erfarenheter av undervisningen, lärandet och rummet. Teoretiskt utgår studien från livsvärldsfilosofi, framför allt vad gäller Martin Heideggers och Gaston Bachelards tankegods, vilka speglas mot och genom studenternas erfarenheter. Resultatanalysen mynnade ut i sju olika teman som samtliga säger något signifikant om digitaliseringen i högre utbildning. Vidare synliggör dessa teman de dikotomier och spänningsfyllda förhållanden som konstituerar rumslighet och hemhörighet i en digitaliserad utbildningskontext.  Finitude unbound – on learning, space and belonging in digitalised higher education Digital learning environments and distance education have over time increasingly come to characterize higher education, and during the covid-19 pandemic the digital transition was radically accelerated. This led to an even more apparent temporal and spatial separation between teachers and students. In the spring of 2021, when students and teachers at universities and colleges had been experiencing this imposed form of online teaching and learning for just over a year, three groups of students were asked to share their experiences of the digital transition through written reflections. The overall purpose of the study was to visualize, critically examine and discuss students’ experiences of the rapid and pervasive digital transformation of the teaching and learning environment. A total of 39 students who studied at universities in Sweden and Iceland, participated. The students were asked to carry out written reflections on a number of open questions related to the digital transformation that their education had undergone, and with a certain focus on their experiences of the (class)room. Theoretically, the study is based on the philosophy of the lifeworld, mainly in accordance with the ideas of Martin Heidegger and Gaston Bachelard, which are reflected against and through the students’ experiences. The results are presented in the form of seven different themes, which together illuminate the students’ experiences of the digital transformation of teaching, learning and the (class)room in higher education. Moreover, the results also point out some of the dichotomies and tensions that constitute spatiality and belonging in an educational context.

Arctic teacher education and educator training : a postcolonial review of online approaches and practices

This manuscript has been written as part of a project, titled: Distance Teaching and Learning in the Arctic Communities (DistARCTIC). The project is funded by UArctic project funding for Network Activities on Arctic Research and Education, allocated by the Danish Agency for Science and Higher Education (DAFSHE) and administered by the UArctic International Secretariat. The project period is 9/2020-12/2023.Peer reviewedPublisher PD

Recycling of Li-Ion Batteries from Industrial Processing: Upscaled Hydrometallurgical Treatment and Recovery of High Purity Manganese by Solvent Extraction

Manganese plays a central role in lithium-ion batteries (LIBs) but its recycling is rarely addressed when compared to other valuable metals present in LIBs, such as Co and Ni. Thus, the main goal of this work was to study and achieve the separation of Mn from Co and Ni by solvent extraction from a leachate obtained from LIBs using hydrochloric acid in an upscaled reactor, which is an innovative aspect of this work. The results confirmed the high selectivity of D2EHPA towards Mn, which could be completely extracted in two stages (0.5 M D2EHPA at pH 2.5). The main co-extracted metals were Al, Cu and Co, but with lower concentrations than Mn. The behavior of minor impurities such as Zn and Mg was also monitored. Scrubbing using manganese chloride was crucial to remove impurities from the loaded organic and prevent their presence in the stripping product, and high O:A ratios negatively affected the scrubbing efficiency. Keeping the concentration of HCl up to 0.5 M in the stripping stage helped to limit the stripping of impurities. Manganese oxide was precipitated as a product with 99.5% purity (with traces of Zn, Cu and Co), which could be reused in the battery value chain

Solvent extraction of cobalt from spent lithium-ion batteries: Dynamic optimization of the number of extraction stages using factorial design of experiments and response surface methodology

The optimization of lithium-ion batteries (LiBs) recycling is crucial not only from a waste management perspective but also to decrease the dependence on imports of critical raw materials. In addition, the diversification of the recycling technologies is very important for better flexibility of the market. This study aims at investigating the recovery of Co from spent LiBs using solvent extraction from a real chloride-based solution obtained after the removal of Mn, which is very rarely reported. Cyanex 272 was used as the extractant and the effect of several variables on the extraction efficiency was considered to model and optimize the separation of Co and Ni. The number of extraction stages directly affects not only the process efficiency but also its cost. Thus, in this work, a novel approach was developed to assist in the selection of the number of extraction stages using a dynamic method based on the factorial design of experiments and response surface methodology combined with the Kremseŕs Equation. This method can assist the process design, decrease the overall cost of the operation, and optimize the separation of Co and Ni in a reduced number of extraction stages. The concentration of Co and Ni in the feed solutions is ∼ 8.3 g/L and 1.9 g/L, respectively. Based on the results, 98% extraction efficiency for Co can be achieved in 1 to 2 extraction stages with low co-extraction of Ni (<5%) when using 0.6–0.8 M Cyanex 272, O:A ratio below 1 and pH ∼ 5, but several combinations of conditions could provide similar results

Transoral Robotic Surgery in the Nordic Countries : Current Status and Perspectives

Background: The five Nordic countries with a population of 27 M people form a rather homogenous region in terms of health care. The management of head and neck cancer is centralized to the 21 university hospitals in these countries. Our aim was to gain an overview of the volume and role of transoral robotic surgery (TORS) and to evaluate the need to centralize it in this area as the field is rapidly developing. Materials and Methods: A structured questionnaire was sent to all 10 Departments of Otorhinolaryngology-Head and Neck Surgery in the Nordic countries having an active programme for TORS in December 2017. Results: The total cumulative number of performed robotic surgeries at these 10 Nordic centers was 528 and varied between 5 and 240 per center. The median annual number of robotic surgeries was 38 (range, 5-60). The observed number of annually operated cases remained fairly low ( Conclusions: The present results showing a limited volume of performed surgeries call for considerations to further centralize TORS in the Nordic countries.Peer reviewe

Teachers' encounters with social media : applications in need of explications

The purpose of this dissertation has been set against the background of both existing research and teachers’ perceptions and experiences with the aim to clarify and better understand what constitutes the teacher’s encounter with social media in teaching. The theoretical starting point in hermeneutical phenomenology in accordance with Heidegger, Gadamer and Ricœur has brought with it not merely the resolve to describe the encounter’s context of meaning, but also the forward-looking striving to point out its possibilities. The study, motivated in particular by the new Swedish IT policy declaration and the new steering documents for compulsory and upper secondary schools, is based on two questions at issue: what perspective towards the encounter between social media and education can be detected in existing research? How does the teacher perceive the use of social media in education? To answer the questions, two sub-studies have been carried out. One comprises a survey of the literature, in which above all international scientific publications with relevance to the use of social media in education have been analysed. This has formed the context for the second part of the study, which comprises individual in-depth interviews with eight teachers working in compulsory schools and upper secondary schools respectively. The results of the study show that the encounter with social media brings both opportunities and challenges. The results therefore to some extent support expectations of the potential of social media in education, such as the encouragement of group processes, pupils’ increased commitment in and influence over the choice of methods, and the forms of presentation and multimodal expression and creativity. The results indicate at the same time apprehension over the user’s exposure that transparency brings, the difficulty of breaching the dominance of the written word, the challenges of the temporal and spatial limits and the changeability and complexity of the sometimes impenetrable technology. The results also indicate undue expectations and an unfortunate approach as characteristics of the teacher’s encounter with the new technology. One example of such an unfortunate approach is the clichéd picture of two separate and homogeneous user groups, i.e. a young generation of expressive super-users and an older generation of digitally impotent immigrants, which creates problems for the teachers’ relationship towards technology use in school. Another is the perception that technology in itself leads to a desired approach and activities, in particular interactivity between pupils. Yet another is the perception that technology in itself leads to a desired approach and activities, in particular interactivity between pupils. Social media should thus be seen as a technology that is as yet incompletely negotiated, a technology to some extent subject to conflicting interests of teachers and pupils, and at the same time – with regard to content and structure, educational goals and self-representation – as an arena for negotiation. This perspective offers an understanding of its meaning in a context of teaching and learning activities, and brings an explanation for the challenges that its use brings. A negotiational perspective of that type underlines the importance of educational aims and teacher strategies. There is in the dissertation a discussion of the possibility to broaden the allocation of responsibilities and roles by not perceiving the teacher as the self evident hub around which the use of the technology is centred. The pupil can instead be permitted to form the starting point for the use and ownership of the technology. The dissertation pays particular attention to empowerment of both the teacher and the pupil to design and redesign personal Web and learning environments, as well as the value of conquering an arena of opportunities for richer, multimodal representations – to express more than that which can be captured through the written word. Social media can in addition be utilised as being-with and as interpretable text. The new technology means not only that we can relatively easy, compared to the last generation’s Web technology, illustrate our own actions, experiences, reflections and opinions: we are in addition surrounded by an increasingly intense stream of other people's expressions and activities. These activities can be interpreted as texts having something meaningful to say about the world, the other person, and myselfGodkänd; 2012; 20120216 (nicekb); DISPUTATION Ämnesområde: Pedagogik Avhandling: Lärares möten med sociala medier applikationer i behov av explikationer Opponent: Professor Per-Olof Erixon, Institutionen för Estetiska ämnen Umeå universitet Ordförande: Professor Eva Alerby Institutionen för Konst, kommunikation och lärande Luleå tekniska universitet Tid: Fredag den 16 mars 2012, kl. 10.00 Plats: D770, Luleå tekniska universitet</p

Cellophane´s working really good ;) : Report on a mobile learning project in upper secondary school

In 2011, a mobile learning project, mLearning, was initiated among students and staff in two upper secondary school classes in northern Sweden. The project's objectives were to help students and staff coordinate their planning, communicate and exchange information, support students' digital competence development, find new ways of expression and create better opportunities for students to learn and for teachers to teach. The purpose of the report was to help create knowledge about how smartphones are used within the framework of a school-related project at the upper secondary school level, and to understand what the project phone and its use means to students and teachers. The report also tried to evaluate the extent to which the mobile learning project met its objectives. The investigation was mainly based on an individual web survey consisting of both quantifiable and open questions. The supporting data also consisted of group interviews with participants and the participants' individual monthly reports regarding their phone use. The hermeneutical processing of the data resulted in three themes. The first theme, "The easy management of information", was derived from the experiences of the ease and speed with which the ever-present mobile phone enables information searches and fact checks. The second theme, "The strengthened communication", primarily focused on strengthened communication but, to some extent, also focused on strengthened relationships, both between teachers and students and between students themselves. The third theme, "The far from obvious meaning of the project mobile", focused on the widely experienced feeling of independence in relation to the technology and the opportunity to personally shape the use of technology. Here, tendencies for marginalisation and a lack of influence regarding the technology and its use were also noted. The results showed that the mobile learning project met its objectives when it came to helping students and staff coordinate their planning, communicate and exchange information. The results for the other objectives were far less clear-cut. The report emphasised that the students experienced an increased sense of security, participation and control which reflected the students experiences of being able to use the project phone whenever, wherever and however they wished. The project phone was, from this perspective, found to have contributed to a beneficial learning situation. While the teachers had a relatively easy time utilising the communicative potential in their contact with students and colleagues, its importance for teaching was not as clear. The report emphasised the value of approaching the issue of mobile phone technology use in schools and its importance for schools from a negotiation and interpretation perspective. In addition to a useful dialogue regarding learning and knowledge objectives, the perspective enables greater participation and a use of technology that allows for individual learning experiences among students. In the search for technology's added value, schools and the education system are recommended to base their approach on general and simple themes, such as the smartphones' basic configuration and standard applications. To the extent that the phone is allowed to become more than a miniature laptop computer, it could become a valuable complement to other technology used in schools. In this way, smartphones can contribute to the efforts to provide students with better opportunities to personally create and show, own and manage. Keywords: mobile learning, smartphone, mobility, context, education technology, teaching, upper secondary school2011 initierades ett mobilt lärandeprojekt, mLearning, bland elever i och personal knuten till två klasser i en gymnasieskola i norra Sverige. Projektets målsättningar var att erbjuda elever och skolpersonal bättre möjligheter till samplanering, kommunikation och informationsutbyte, stödja eleven i sin digitala kompetensutveckling, stimulera till fler uttryckssätt samt att skapa rikare möjligheter för elevers lärande och lärares undervisning. Syftet med rapporten var att bidra till kunskapen om hur den smarta mobiltelefonen kommer till användning inom ramarna för ett skolrelaterat projekt på gymnasienivå samt att förstå vad projekttelefonen och användningen av denna betyder för elever och lärare. Därtill avsåg rapporten besvara hur det mobila lärandeprojektet har svarat mot det mobila lärandeprojektets syften. Undersökningen baserades till övervägande del på en individuell webbenkät bestående av såväl kvantifierande som öppna frågor. Underlaget bestod även av samtal med deltagare i grupp och deltagarnas individuella månadsrapportering kring telefonanvändningen. Den hermeneutiskt grundade bearbetningen materialet mynnade ut i tre teman. Det första temat ”Den enkla informationshanteringen” härrörde från upplevelserna av den lätthet och snabbhet med vilken den alltid närvarande mobiltelefonen möjliggör informationssökningar och faktakontroll. I det andra temat, ”Den stärkta kommunikationen” uppmärksammades särskilt den stärkta kommunikationen – men i viss mån även stärkta relationer – mellan såväl lärare och elev, som elever emellan. Det tredje temat, ”Projektmobilens långt ifrån självklara mening”, fokuserade de utbredda upplevelserna av självständighet i förhållandet till tekniken och möjligheter att själv forma teknikanvändningen. Här påvisades även upplevelser av marginalisering och ett ringa inflytande över tekniken och dess användningssätt. Resultaten visade det mobila lärandeprojektet uppnådde målsättningen att stärka elevernas och skolpersonalens samplanering, kommunikation och informationsutbyte. Resultaten ifråga om de övriga målsättningarna var långt mindre entydiga. I rapporten framhölls elevernas erfarenheter av en ökad trygghet. delaktighet och egenkontroll vilka återspeglade elevernas upplevelser av att kunna använda projekttelefonen när, var och hur man vill. Projekttelefonen befanns utifrån detta perspektiv ha bidragit till en gynnsammare lärsituation. Medan lärarna hade förhållandevis lätt att tillvarata mobiltelefonens kommunikativa värden i kontakten med elever och kollegor, uppfattades dess betydelse för undervisningen inte lika självklar. I rapporten framhölls värdet i att närma sig frågan om mobilteknikens användning i och betydelse för skolan utifrån ett förhandlings- och tolkningsperspektiv. Perspektivet möjliggör, förutom en fruktbar dialog kring lärandet och kunskapsmålen, en större delaktighet och en teknikanvändning som medger individuella lärupplevelser bland eleverna. I sökandet efter teknikens mervärden förordades skola och utbildning ta utgångspunkt i det generella och enkla, i den smarta mobiltelefonens grundkonfiguration och mobilteknikens standardapplikationer. I den mån den smarta telefonen tillåts bli något annat än en bärbar dator i miniatyr kan den komma att bli ett värdefullt komplement till den övriga teknikanvändningen i skolan. På så sätt kan den smarta mobiltelefonen bidra till strävandena efter att ge den lärande bättre förutsättningar att själv göra och visa, äga och hantera.Keywords: mobile learning, smartphone, mobility, context, education technology, teaching, upper secondary schoolGodkänd; 2013; 20130524 (nicekb

Studenters erfarenheter av att använda mobil teknik och öppna webbresurser i en distansbaserad masterutbildning

Godkänd; 2014; 20141008 (andbra