Forskning

• Material för miljön
• Helt biobaserade membran/filter för vattenrening
• Ytkemi och interaktioner, mekaniska egenskaper, viskoelastiska egenskaper, in situ SAXS
• Atomkraftsmikroskopi (förstå egenskaper i nanoskala, kolloidal sond)

Material för hälsa

• Biobaserat material för medicinska tillämpningar
• Vävnadsteknik, sårförband, antifouling och antibakteriella material

Syntes- och bearbetningsmetoder för hållbara material

• Nanocellulosa och nanochitin isolering och karakterisering
• Design av återvinning och cirkularitet av material
• Bearbetning och karakterisering av bionanokompositer, hybrider och tvärbundna polymerer

Pågående projekt

Katalytisk fraktionering av skogsrester och återvunna textilier för att generera material och kemikalier)

Mistra Safechem, 2020-2024

Forskningsprogrammet Safe and Efficient Chemistry by Design (SafeChem) syftar till att förbättra industrins förmåga att minska farlig kemikalieexponering för människor och miljön genom implementering av det verktyg som utvecklats inom programmet.

Cirkularitet av material och förlängning av värdekedjan för producerade varor är ett område av yttersta relevans i gröna och hållbara industrier och samhällen. Den här uppgiften kommer att fokusera på återvinning och omvandling av bomullsbaserade textilier samt fraktionering och omvandling av lågvärderade lignocellulosaråvaror som toppar, rötter och grenar från skogsbruket till kemikalier, nanocellulosa och förnybara produkter framställda av dessa material.

Projektet sker i samarbete med textil-, skogs- samt biobränsle- och kemisk industri.

Mistra, Smarta material, TERRACLEAN 2017-2024
www.mistraterraclean.com

Oavsett källan måste reningstekniken förbättras. Inte minst eftersom dagens lösningar som ofta bygger på olika typer av filter och membran inte kan fånga in alla typer av föroreningar, framförallt inte ämnen som förekommer i små mängder. Här bidrar vi med lösningar för att utveckla smarta material ör att utveckla smarta material för borttagning av kemiska ämnen, avfall och föroreningar från omgivande vatten och luft i miljön och industriavlopp.

Tidigare finansiering

3D-utskrift av biobaserade filter funktionaliserade med nanocellulosa för vattenrening

Wallenberg Wood Science Center Finansiering, Functional Materials Research vid Stockholms universitet, 2019-2022 (www.wwsc.se)

Det övergripande projektet syftar till att utveckla nya vägar för att bearbeta och producera filter genom 3D-utskrivet material. Den aktiva delen i filtren kommer att baseras på nanokompositer med nanocellulosa som komponenter, för att belysa hur porositeten och ytkemin kan skräddarsys för att ge högt vattenflöde, hög separationseffektivitet och långtidsstabilitet i våt miljö.

Förstå nanocellulosahybridmembran med hjälp av avancerad atomkraftsmikroskopi (AFM), Raman/NMR-spektroskopi, röntgenspridning och beräkningskemi

Vetenskapsrådet (2018-2021)

Projektet utvecklar experimentella procedurer för att undersöka biobaserade hybrider i flytande medium/våta förhållanden med hjälp av atomkraftsmikroskopi och spektroskopi och in situ röntgenspridning, kombinerat med beräkningskemi, är tänkt i projektet för att utvärdera och förutsäga självmontering mellan nanocellulosa och andra nanopartiklar och förstå hur de självmonterade morfologierna driver porstrukturbildningen och adsorptionen i biobaserade membran och filter som används för vattenrening.

Projektkoordinator: FP7-NMP-2011-SMALL-5, förslagets referensnummer: 280519-2 2011, budget: 4 miljoner euro, samordnare, 2012-2016

Principal Investigator:

• Wallenberg Wood Science Center Finansiering, Funktionell materialforskning vid Stockholms universitet, 2015-2019
• Stockholms universitets fakultetsstöd, 2015-2019
• VR 2013, 2014-2017.; Svenska forskningslänkar
• Internationella forskningsanslag, Sydafrika, 2009-2011
• Svenska forskningslänkar, Internationella forskningsanslag, Indien 2009-2011
• Nanomembran för rening av gaser och vätskor, Innovationsbron, (2009)
• Biobaserade byggnadsställningar, membran och hydrogeler för förbättrad sårläkning och benregenerering (Bioheal) 
• Svenska forskningslänkar, Internationellt samarbete: 2017-2020

Partner: CEREAL (ERANET-SUSFOOD, 2014–2017; n-POSSCOG, nr: 2011-02071 MNT-ERA.NET

Transnationell utlysning 2011; H2020, NanoTextsurf, 2017-2020. www.nanotextsurf.eu

I urval från Stockholms universitets publikationsdatabas

• Citrated cellulose nanocrystals from post-consumer cotton textiles

  2023. Maria-Ximena Ruiz-Caldas (et al.). Journal of Materials Chemistry A

  Artikel

  We propose a new method for the extraction of cellulose nanocrystals (CNCs) from post-consumer cotton textiles through surface functionalization followed by mechanical treatment. Cotton-based textiles were esterified using an 85 wt% solution of citric acid at 100 degrees C, then further fibrillated in a microfluidizer. The final product, citrated cellulose nanocrystals (CitCNCs), was a dispersion of needle-like nanoparticles with high crystallinity. Up to 78 wt% of the cotton fabric was converted to CitCNCs that exhibited higher yields and a higher surface group content than CNCs extracted through H2SO4 hydrolysis, although CitCNCs showed a broader size distribution and decreased thermal stability. Experimental data supported by DFT calculations showed that the carboxyl groups on the CitCNC surface are bonded to cellulose by mono or diester linkages. An early-stage life cycle assessment (LCA) was performed to evaluate the environmental impact of using discarded textiles as a source of cellulose and analyze the environmental performance of the production of CitCNCs. Our work showed a significant reduction in the environmental burden of CNC extraction using post-consumer cotton instead of wood pulp, making clothing a good feedstock. The environmental impact of CitCNC production was mainly dominated by citric acid. As a proof of concept, around 58 wt% of the citric acid was recovered through evaporation and subsequent crystallization, which could reduce climate impact by 40%. With this work, we introduce a catalyst-free route to valorize textiles with the extraction of CitCNCs and how conducting LCA in laboratory-scale processes might guide future development and optimization.

  Läs mer om Citrated cellulose nanocrystals from post-consumer cotton textiles

• In-Situ Growth of Metal Oxide Nanoparticles on Cellulose Nanofibrils for Dye Removal and Antimicrobial Applications

  2020. Luis Valencia (et al.). ACS Applied Nano Materials 3 (7), 7172-7181

  Artikel

  Nanocellulose is known to act as a platform for the in-situ formation of metal oxide nanoparticles, where the multiple components of the resultant hybrids act synergistically toward specific applications. However, typical mineralization reactions require hydrothermal conditions or addition of further reducing agents. Herein, we demonstrate that carboxylated cellulose nanofibril-based films can spontaneously grow functional metal oxide nanoparticles during the adsorption of heavy metal ions from water, without the need of any further chemicals or temperature. Despite the apparent universality of this behavior with different metal ions, this work focuses on studying the in-situ formation of copper oxide nanoparticles on TOCNF films as well as the resultant hybrid films with improved functionality toward dye removal from water and antimicrobial activity. Using a combination of cutting-edge techniques (e.g., in-situ SAXS and QCMD) to systematically follow the nanoparticle formation on the nanocellulosic films in real time, we suggest a plausible mechanism of assembly. Our results confirm that carboxylated cellulose nanofibril films act as universal substrate for the formation of metal oxide nanoparticles, and thus hybrid nanomaterials, during metal ion adsorption processes. This phenomenon enables the upcycling of nanocellulosic materials through multistage applications, thus increasing its sustainability and efficiency in terms of an optimal use of resources.

  Läs mer om In-Situ Growth of Metal Oxide Nanoparticles on Cellulose Nanofibrils for Dye Removal and Antimicrobial Applications

• Unlocking the potential of post-consumer garments as a source of nanocellulose

  2024. Maria-Ximena Ruiz-Caldas, Varvara Apostolopoulou Kalkavoura, Aji P. Mathew. Cell Reports Physical Science 5 (2)

  Artikel

  Discarded garments contribute to an environmental crisis worldwide, prompting the development of new strategies for recycling and upcycling. In this work, we present the extraction of nanocellulose from textiles as an underexplored route for upcycling textile garments made of cotton. We summarize the current state of textile waste management worldwide, discuss strategies for extracting nanocellulose from cotton -based textiles, and outline the associated challenges and outlooks in this field. We further aim to highlight the opportunities and advantages of using cotton as a nanocellulose source and stimulate further research in this area.

  Läs mer om Unlocking the potential of post-consumer garments as a source of nanocellulose

• Lignin-first biorefining of Nordic poplar to produce cellulose fibers could displace cotton production on agricultural lands

  2022. Anneli Adler (et al.). Joule 6 (8), 1845-1858

  Artikel

  Here, we show that lignin-first biorefining of poplar can enable the production of dissolving cellulose pulp that can produce regenerated cellulose, which could substitute cotton. These results in turn indicate that agricultural land dedicated to cotton could be reclaimed for food production by extending poplar plantations to produce textile fibers. Based on climate-adapted poplar clones capable of growth on marginal lands in the Nordic region, we estimate an environmentally sustainable annual biomass production of ∼11 tonnes/ha. At scale, lignin-first biorefining of this poplar could annually generate 2.4 tonnes/ha of dissolving pulp for textiles and 1.1 m³ biofuels. Life cycle assessment indicates that, relative to cotton production, this approach could substantially reduce water consumption and identifies certain areas for further improvement. Overall, this work highlights a new value chain to reduce the environmental footprint of textiles, chemicals, and biofuels while enabling land reclamation and water savings from cotton back to food production.

  Läs mer om Lignin-first biorefining of Nordic poplar to produce cellulose fibers could displace cotton production on agricultural lands

• 3D printed polylactic acid (PLA) filters reinforced with polysaccharide nanofibers for metal ions capture and microplastics separation from water

  2023. Natalia Fijoł (et al.). Chemical Engineering Journal 457

  Artikel

  The need for multifunctional, robust, reusable, and high-flux filters is a constant challenge for sustainable water treatment. In this work, fully biobased and biodegradable water purification filters were developed and processed by the means of three-dimensional (3D) printing, more specifically by fused deposition modelling (FDM).

  The polylactic acid (PLA) – based composites reinforced with homogenously dispersed TEMPO-oxidized cellulose nanofibers (TCNF) or chitin nanofibers (ChNF) were prepared within a four-step process; i. melt blending, ii. thermally induced phase separation (TIPS) pelletization method, iii. freeze drying and iv. single-screw extrusion to 3D printing filaments. The monolithic, biocomposite filters were 3D printed in cylindrical as well as hourglass geometries with varying, multiscale pore architectures. The filters were designed to control the contact time between filter’s active surfaces and contaminants, tailoring their permeance.

  All printed filters exhibited high print quality and high water throughput as well as enhanced mechanical properties, compared to pristine PLA filters. The improved toughness values of the biocomposite filters clearly indicate the reinforcing effect of the homogenously dispersed nanofibers (NFs). The homogenous dispersion is attributed to the TIPS method. The NFs effect is also reflected in the adsorption capacity of the filters towards copper ions, which was shown to be as high as 234 and 208 mg/gNF for TCNF and ChNF reinforced filters, respectively, compared to just 4 mg/g for the pure PLA filters. Moreover, the biocomposite-based filters showed higher potential for removal of microplastics from laundry effluent water when compared to pure PLA filters with maximum separation efficiency of 54 % and 35 % for TCNF/PLA and ChNF/PLA filters, respectively compared to 26 % for pure PLA filters, all that while maintaining their high permeance.

  The combination of environmentally friendly materials with a cost and time-effective technology such as FDM allows the development of customized water filtration systems, which can be easily adapted in the areas most affected by the inaccessibility of clean water.

  Läs mer om 3D printed polylactic acid (PLA) filters reinforced with polysaccharide nanofibers for metal ions capture and microplastics separation from water

Visa alla publikationer av Aji Mathew vid Stockholms universitet