Periodic Reporting for period 1 - BIOCATMAG (CATALYSIS IN AQUEOUS SOLUTION BY MAGNETIC INDUCTION: BIOMASS VALORIZATION)
Periodo di rendicontazione: 2023-06-01 al 2025-05-31
BIOCATMAG brings these two challenges together. The project explores the valorisation of biomass using a cutting-edge method called magnetically induced catalysis, where specifically designed magnetic catalysts heat up very fast, efficiently and generate highly localised hot spots when exposed to an alternating magnetic field (AMF). In this way, the technology has the potential to enable chemical reactions to happen exactly where and when needed, without heating the entire reactor. This not only saves energy and adapts to fluctuating energy sources, but also enables more selective and, consequently, more sustainable chemical transformations. Despite its promise, magnetically induced catalysis remains in its infancy, particularly in aqueous-phase systems.
Therefore, BIOCATMAG focuses on three main objectives that target key chemical transformations in water and mild conditions. First, upgrading a cellulose-derived molecule (levoglucosenone) into greener alternatives to solvents and plastics; creating food- and pharma-relevant molecules directly from sugar and ammonia; and converting raw cellulose into high-value furan molecules using a single water-based process. In the last case, the project attempts to take advantage of the highly localized heating produced at the surface of magnetic nanoparticles to drive one reaction, while a second reaction occurs simultaneously in the cooler bulk liquid using a separate, non-magnetic catalyst, thereby allowing two distinct chemical steps to take place at two different temperatures, within the same reactor.
By combining smart catalyst design with magnetic heating, BIOCATMAG aims to demonstrate that chemical production can be cleaner, more energy-efficient, and better aligned with a future powered by renewable energy. The project's results offer hope for continuing to explore new technologies in green chemistry, reducing reliance on fossil fuels, and supporting Europe’s broader goals for climate action and sustainable innovation.
For LGO valorization, magnetic FeNi nanoparticles encapsulated inside a N-doped carbon (FeNi@N–C) enabled high-yield hydrogenation under AMF (320 kHz), producing high yields of Cyrene or levoglucosanol in water by tuning the field amplitude (40 vs 63 mT). The high catalytic performance was attributed to the combination of a hard-magnetic Fe core and a catalytically active FeNi alloy on the outer surface, as well as the structural protection and chemical stabilisation offered by the N-doped carbon shell.
In the pyrazine case study, BIOCATMAG first developed W oxycarbide-based catalysts, that enabled the direct conversion of glucose and ammonia into N-containing heterocycles (pyrazines) under conventional heating. Operating at 180 ºC, the system produced a wide array of pyrazines and was reusable, offering a more sustainable alternative to conventional routes. Then, the project moved toward integrating these systems with iron wool for magnetically induced catalysis. Preliminary results confirmed the feasibility of transferring this complex reaction to magnetic induction conditions, marking a significant step toward a more sustainable, energy-efficient synthetic route to pyrazines.
The project also explored the tandem conversion of glucose to furan derivatives, utilising dual-zone temperature control with both magnetic and non-magnetic catalysts. While full tandem conversion remains a future goal, the project successfully demonstrated glucose isomerization under AMF using engineered oxide-coated iron wool catalysts. Moreover, a family of water-soluble nanoparticles stabilized by sulfonated N-heterocyclic carbene ligands was developed for selective HMF hydrogenation in water. These catalysts exhibited tunable selectivity under 5 H2 bars depending on metal and temperature: Ru-based nanoparticles yielded BHMF at 30 ºC, as well as RuZn at 100 ºC, Pd yielded BHMTHF at 40 ºC, Ir produced oxidized cyclopentenones at 140 ºC, and RuIr2 gave HHD at the same temperature.
In parallel, the project inspired new research directions, including the use of Ru-decorated CoNi nanoparticles for the hydroprocessing of lignin-derived model compounds under AMF. Moreover, an ongoing research line focuses on exploring how the size of the Ru decoration, i.e. from nanoparticles to isolated atoms, can be tuned via organometallic precursors and thermal or magnetic treatments to enhance hydrogen activation.
BIOCATMAG also contributed to an exhaustive and broader understanding of magnetically induced catalysis through a peer-reviewed review in ChemCatChem and a book chapter in the Springer Topics in Organometallic Chemistry, both of which positioned the technology at the forefront of sustainable chemical technologies.
The first was the development of a highly selective, magnetically induced hydrogenation process for levoglucosenone (LGO) to levoglucosanol. Using FeNi@N–C nanoparticles under an alternating magnetic field (320 kHz), the reaction proceeded in water, yielding up to 99% of levoglucosanol, simply by adjusting the magnetic field amplitude, which probably represents the most relevant result up to date in the production of this chemical, considering the quantitative yield, the low H2 pressure (5 bar), and the use of base metals. The catalyst was robust and recyclable, operating without external heating and demonstrating how magnetic nanoparticles can serve as both heat sources and active catalytic sites.
The second key result was the synthesis of pyrazines from glucose and ammonia, avoiding toxic reagents and fossil-derived feedstocks. A tungsten oxycarbide-based system developed within the project enabled this transformation in water at 180°C, yielding ~20% of pyrazines with good reusability. This stands as the only example of an aqueous-phase route from glucose to N-heterocycles of the pyrazine type with reusable solid catalysts.
Finally, BIOCATMAG developed a versatile family of water-soluble Ru-based nanoparticles stabilized by sulfonated NHC ligands for the hydrogenation of HMF. These catalysts operated under mild temperatures and low H2 presures (5 bar), without organic solvents and showed tunable selectivity depending on composition. Ru and RuZn-based nanoparticles achieved almost quantitative yields to 2-5-bishydroxymethylfurfural (2,5-BHMF), maintaining activity over time. Moreover, Ir-based nanoparticles unlocked an unreported selectivity toward oxidized cyclopentenones, while RuIr2-based ones directed the reaction toward HHD formation.
Although the full two-step glucose-to-HMF-to-BHMF conversion remains under development, the project laid a strong foundation. BIOCATMAG’s collaborators in Seville are now well positioned to further optimize the initial glucose conversion to HMF step and continue advancing the dual-temperature reactor concept.