Journal of Natural Fibers (Nov 2022)

Extraction of Nanocellulose from Yerba Mate Residues Using Steam Explosion, TEMPO-mediated Oxidation and Ultra-fine Friction Grinding

  • Ruan Ezequiel Gemmer,
  • Cleide Borsoi,
  • Betina Hansen,
  • Marcos Aurélio Dahlem Júnior,
  • Edson Luiz Francisquetti,
  • Lilian Vanessa Rossa Beltrami,
  • Ademir José Zattera,
  • André Luis Catto

DOI
https://doi.org/10.1080/15440478.2021.1994095
Journal volume & issue
Vol. 19, no. 15
pp. 10539 – 10549

Abstract

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In this work, we evaluated the extraction of nanocellulose from agro-industrial residue of yerba mate (YM, Ilex paraguariensis, St.Hil) sticks through chemical (bleaching and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation), physical (steam explosion) and mechanical (ultra-fine friction grinding) treatments, divided into three distinct sequences for method comparison. The results showed that steam explosion as the initial treatment step makes an increase of up to 23% in the crystallinity index of cellulose nanofiber (CNF) in relation to the raw sample. The TEMPO-mediated oxidation resulted in more dispersed CNF, verified by transmission electron microscopy (TEM). Samples treated by steam-explosion and ultrafine grinding showed a higher yield in relation to steam-explosion and oxidative treatment (24.3% versus 16.2% respectively). CNFs with a diameter of 6 nm and a length range of 2200 to 2600 nm were obtained.

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