TY - JOUR
T1 - Efficient extraction of carboxylated nanocellulose from ionoSolv pulps with alkaline H2O2 assisted oxidation
AU - Rafat, Aida Abouelela
AU - Verdía Barbará, Pedro
AU - Ullah, Asim
AU - Kontturi, Eero
AU - Law, Robert V.
AU - Hallett, Jason P.
N1 - Publisher Copyright:
© The Author(s) 2024.
PY - 2024/12/11
Y1 - 2024/12/11
N2 - We report a simple procedure to produce carboxylated cellulose nanocrystals (CNCs) from grassy biomass (Miscanthus X Giganteus) using a two-step approach consisting of biomass fractionation with a protic ionic liquid followed by oxidation of the resulting cellulose-rich pulps with H2O2. The impact of the fractionation severity on the composition, structure, size, thermal stability, crystallinity, and degree of polymerization of the CNCs was evaluated. It was found that fractionation severity had a large impact on the pulp purity and its reactivity during the oxidation stage. Nevertheless, the impact on the properties of the final CNCs was small. CNCs were recovered as suspensions of negatively charged, electrostatically stable, needle-like CNCs with a lower degree of crystallinity (58–61%) compared to the precursor pulps (65–69%). The presence of carboxyl groups on the surface of the CNCs facilitated the stability of the suspensions but also caused a slight decrease in the thermal stability of the CNCs. A milder oxidation process followed by ultrasonication allowed us to maximize the production of CNCs while better preserving the degree of crystallinity of the cellulose (63%).
AB - We report a simple procedure to produce carboxylated cellulose nanocrystals (CNCs) from grassy biomass (Miscanthus X Giganteus) using a two-step approach consisting of biomass fractionation with a protic ionic liquid followed by oxidation of the resulting cellulose-rich pulps with H2O2. The impact of the fractionation severity on the composition, structure, size, thermal stability, crystallinity, and degree of polymerization of the CNCs was evaluated. It was found that fractionation severity had a large impact on the pulp purity and its reactivity during the oxidation stage. Nevertheless, the impact on the properties of the final CNCs was small. CNCs were recovered as suspensions of negatively charged, electrostatically stable, needle-like CNCs with a lower degree of crystallinity (58–61%) compared to the precursor pulps (65–69%). The presence of carboxyl groups on the surface of the CNCs facilitated the stability of the suspensions but also caused a slight decrease in the thermal stability of the CNCs. A milder oxidation process followed by ultrasonication allowed us to maximize the production of CNCs while better preserving the degree of crystallinity of the cellulose (63%).
KW - Biomass
KW - Cellulose nanocrystals (CNCs)
KW - HO oxidation
KW - Ionic liquids
KW - Nanocellulose
KW - Ultrasonication
UR - http://www.scopus.com/inward/record.url?scp=85212109473&partnerID=8YFLogxK
U2 - 10.1007/s10570-024-06319-4
DO - 10.1007/s10570-024-06319-4
M3 - Article
AN - SCOPUS:85212109473
SN - 0969-0239
JO - Cellulose
JF - Cellulose
ER -