Ученые нашли экологичную замену хлориту натрия для производства целлюлозных нановолокон из свекловичной пульпы

Abstract Background A simple, one-pot process can be applied to sugar beet pulp (SBP), a low-lignin secondary biomass material, to produce cellulose nanofibers (CNF). However, this process uses sodium chlorite (SC) for a key bleaching step. This work explores both the replacement of SC with the environmentally friendly peracetic acid (PAA), both exogenous and in situ generated, and how the choice of peroxyl or free-radical bleaching mechanism affects this reaction. Results It was found that PAA-bleached CNFs (PAA-CNF) were very close to SC-bleached CNF (SC-CNF) in terms of colour (~67% relative brightness index), and that whilst the peroxyl mechanism brighten the pulp, free-radical bleaching darkened the pulp. PAA and Fenton-oxidised CNFs were more enriched in lignin due to loss of matrix polysaccharides than SC-oxidised CNF (9, 10 and 4%) but were in turn more viscous (4500, 2500 and 2000 cP). The CNFs all showed stability incipiently, with zeta potentials from − 17 to − 23 mV, and increased the aspect ratio of the fibrils in comparison to the unoxidised CNF. Moreover, the in situ generation of PAA-CNFs was of similar quality to CNF bleached by exogenous PAA. Conclusions In this study, we demonstrate three successful alternatives for replacing SC in our CNF production method. After PAA oxidation the lignin remains, yet the resultant CNF suspensions are more viscous and equal in brightness to SC-CNF. Overall, this work shows how we can innovate an entirely chlorine-free, enzyme-mediated production processing that represents an advance for the safety and reduction of toxicity of the process, and furthers the development of upcycling of secondary biomass into sustainable alternatives for biomaterials. Graphical Abstract Similar content being viewed by others Abbreviations - SBP: - Sugar beet pulp - TAED: - Tetraacetylethylenediamine - CNF: - Cellulose nanofibers - SC: - Sodium chlorite - HP: - Hydrogen peroxide - PAA: - Peracetic acid - SPC: - Sodium percarbonate - %w/w : - Weight/weight - %v/v : - Volume/volume - AMSA: - Array-based microfibril surface assessment - PBS: - Phosphate-buffered saline - BCIP: - 5-Bromo-4-chloro-3-indolylphosphate - NBT: - Nitro-blue tetrazolium chloride - SEM: - Scanning electron microscopy - FEG: - Field emission gun - RBI%: - Relative Brightness index - SBPe: - SBP, enzymatically digested - SC-SBPe: - Sodium chlorite-oxidised SBPe - PAA-SBPe: - Peracetic acid-oxidised SBPe - HP.F-SBPe: - Hydrogen peroxide-Fenton-oxidised SBPe - G′: - Storage modulus - G″: - Loss modulus - ZP: - Zeta potential - TriA: - Triacetin - GOx: - Glucose oxidase Acknowledgements This work was supported by a Grant from the Novo Nordisk Foundation: NNF22OC0072911. Funding Open access funding provided by Copenhagen University. This work was supported by a Grant from the Novo Nordisk Foundation: NNF22OC0072911. Ethics declarations Competing interests The authors declare no competing interests. Additional information Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary Information Rights and permissions Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/. About this article Cite this article Donohoe, C., Engquist, E., Carstens, N. et al. Exploring totally chlorine-free bleaching methods to produce sugar beet pulp cellulose nanofibers. Biotechnol. Biofuels Bioprod. (2026). https://doi.org/10.1186/s13068-026-02806-x - Received: - Accepted: - Published: - DOI: https://doi.org/10.1186/s13068-026-02806-x