Real-Time In Situ Monitoring of Reactive Extrusion
Source: BAM
Mechanochemistry is a promising and sustainable approach where mechanical force drives chemical reactions, significantly reducing or eliminating the need for solvents. Despite its "green" potential attracting growing interest from both the research and industrial communities, most prior studies have relied on ball mills, which limit production to laboratory scales. For industrial-scale applications, extrusion offers a more viable alternative by enabling continuous processing and scalability. However, until now, no effective monitoring method has existed to control and optimize the complex reactions within extruders.
This study introduces energy-dispersive X-ray diffraction (EDXRD) as an advanced in situ monitoring technique for reactive extrusion. Developed at the PSICHE beamline at the French synchrotron facility SOLEIL, EDXRD provides time- and spatially resolved data on phase compositions and transformations, offering unprecedented control over the extrusion process. To demonstrate the broad applicability of this method, three model systems were investigated: an inorganic metathesis reaction, the synthesis of a metal-organic framework, and the formation of organic cocrystals. These systems were chosen to represent a wide range of industrially relevant mechanochemical reactions, each with unique material properties, such as scattering power and crystallinity.
EDXRD enabled real-time monitoring of key reaction parameters, including phase transitions, intermediate and side products, and crystal growth dynamics. The technique provided valuable insights into the formation of solid-state products under both dry and solvent-assisted conditions, delivering detailed mechanistic information that allows for more precise control of the extrusion process. Compared to traditional ex situ monitoring methods, EDXRD offers faster and more efficient process optimization, reducing the need for costly trial-and-error approaches.
Ultimately, these findings highlight the potential mechanochemistry as a practical, green alternative to traditional solvent-based processes in large-scale chemical manufacturing.
Lighting up industrial mechanochemistry: Real-time in situ monitoring of reactive extrusion using energy-dispersive X-ray diffraction
Nikita Y. Gugin, Kirill V. Yusenko, Andrew King, Klas Meyer, Dominik Al-Sabbagh, Jose A. Villajos, Franziska Emmerling
Chem, 2024