Reviewed by Lexie CornerJan 15 2025
Rice College researchers printed a research within the journal Carbon, demonstrating that carbon nanotube (CNT) fibers may be recycled with out shedding their construction or properties, supporting efforts towards a extra sustainable and round financial system.
Carbon nanotube fibers. Picture Credit score: Jeff Fitlow/Rice College
This discovering positions CNT fibers as a sustainable various to conventional supplies comparable to metals, polymers, and bigger carbon fibers, that are difficult to recycle.
Recycling has lengthy been a problem within the supplies trade—metals recycling is usually inefficient and vitality intensive, polymers are likely to lose their properties after reprocessing, and carbon fibers can’t be recycled in any respect, solely downcycled by chopping them up into brief items.
Matteo Pasquali, A.J. Hartsook Professor of Chemical and Biomolecular Engineering, Supplies Science and NanoEngineering and Chemistry, Rice College
He added, “As CNT fibers are being scaled up, we asked whether and how these new materials could be recycled in the future so as to proactively avoid waste management problems that emerged as other engineered materials reached large-scale use. We expected that recycling would be difficult and would lead to significant loss of properties. Surprisingly, we found that carbon nanotube fibers far exceed the recyclability potential of existing engineered materials, offering a solution to a major environmental issue.”
Utilizing chlorosulfonic acid, a typical industrial solvent, the group dissolved fiber-grade business CNTs to provide solution-spun CNT fibers. Evaluating the influence of various materials sources on the fiber manufacturing course of and fiber properties was essential, as end-of-life recycling typically entails combining supplies from numerous producers utilizing totally different manufacturing strategies.
Fibers constructed from several types of CNTs from numerous producers have been first processed into distinct single-source virgin fibers after which recycled by mixing them with chlorosulfonic acid. Notably, the 2 fibers totally redissolved with out separating into distinct liquid phases. The redissolved materials was spun right into a mixed-source recycled fiber with the identical construction and alignment because the virgin fiber.
By utilizing two totally different sources of carbon nanotubes, we ensured that our recycling course of was consultant of real-life circumstances. Remarkably, the recycled fibers demonstrated equal mechanical energy, electrical conductivity, thermal conductivity and alignment, which is unprecedented within the subject of engineered supplies.
Michelle Durán-Chaves, Research Co-First Creator and Graduate Scholar, Rice College
The research recognized a number of key findings that spotlight CNT fibers as a viable materials for sustainable practices. Foremost amongst these is their full recyclability. Not like conventional supplies comparable to polymers and carbon fibers, which degrade in high quality throughout recycling, CNT fibers retain 100 % of their unique properties after recycling.
This preservation of high quality means CNT fibers can be utilized and reused in demanding purposes with out compromising efficiency, thus extending their lifecycle and lowering the necessity for brand spanking new uncooked supplies.
Ivan R. Siqueira, Research Co-First Creator and Affiliate Professor, Pontifícia Universidade Católica
The effectivity of the recycling course of is one other important benefit. The researchers noticed that CNT fiber recycling is way extra environment friendly than typical metallic and polymer recycling strategies, which frequently contain excessive vitality consumption, hazardous chemical compounds, or labor-intensive sorting.
In distinction, CNT fibers may be recycled with out sorting, as fibers from numerous sources may be mixed to provide high-quality recycled supplies. At scale, this simple recycling course of might considerably cut back waste, vitality use, and carbon dioxide emissions related to manufacturing.
Durán-Chaves added, “The ability to fully recycle CNT fibers has broad implications for industries like aerospace, automotive, and electronics. We hope this could pave the way for fully recyclable composites in aircraft, vehicles, civil infrastructures, and more, ultimately reducing environmental impacts across a wide range of sectors.”
The research’s co-authors embrace Rice graduate alumni Oliver Dewey, now with DexMat; Steven Williams; Cedric Ginestra, now with LyondellBasell; Yingru Track, at present a postdoctoral fellow at Purdue College; Rice undergraduate alumnus Juan De La Garza, now with Axiom House; and Geoff Wehmeyer, assistant professor of mechanical engineering at Rice.
This analysis is a part of the Carbon Hub, a Rice-led initiative aiming for a zero-emission future by effectively and sustainably co-producing superior carbon supplies and clear hydrogen from hydrocarbons.
The research acquired funding from the Division of Vitality’s Superior Analysis Venture Company, the Air Pressure Workplace of Scientific Analysis, the Robert A. Welch Basis, the Nationwide Science Basis, the Novo Nordisk Basis CO2 Analysis Middle, the Ken Kennedy Institute Graduate Fellowship from Schlumberger and Rice, and the Riki Kobayashi Fellowship from Rice’s chemical and biomolecular engineering division.
Rice researchers unveil analysis in carbon nanotube recycling, paving approach for sustainable materialsPlay
Video Credit score: Rice College
Journal Reference:
Siqueira, I. R., et. al. (2024) Absolutely recyclable carbon nanotube fibers. Carbon. doi.org/10.1016/j.carbon.2024.119899
