Doctoral candidate Elijah Garcia from Aalto University, recently visited the Federal Institute for Materials Research and Testing (BAM), Germany. This collaboration aimed to delve deeper into mechanochemistry and to develop methods for monitoring the reactive extrusion of lignin.
During Elijah's stay, he replicated their lignin modification system using various mechanochemical tools such as ball mills and extruders following the solventless method for functionalizing lignin. He then analyzed the resulting products with standard techniques for lignin analytics (GPC, FTIR, NMR). While these ex-situ methods are precise and comprehensive, they come with limitations because they require removing samples from their reaction environment and dissolving lignin, which can be both laborious and may introduce sampling artifacts.
To overcome these challenges, they implemented real-time spectroscopy to monitor changes in lignin directly within the extruder. This approach proved instrumental in understanding how different extrusion parameters influenced the modification process, which in turn led to improvements in upscaling to yield a hundred grams of modified lignin—an essential step towards industrial production.
Elijah’s research visit allowed the formation of a valuable collaboration between Aalto University and BAM. By integrating Aalto’s proficiency in lignin chemistry with BAM’s expertise in mechanochemistry, innovative and sustainable processes for manufacturing bio-based materials were developed. These new methods can be translated to other bio-based systems, potentially benefitting the broader biomass-based research community and industries.
