Isolation of cellulose from Arundo donax L. using deep eutectic solvent for the preparation of regenerated fiber

Arundo donax L. is a promising lignocellulosic biomass source for sustainable cellulose fiber production. However, pulping and spinning processes often rely on environmentally harmful solvents. Herein, A full-process deep eutectic solvent (DES) strategy is reported for efficient cellulose isolation from Arundo donax L. and direct fabrication of regenerated cellulose fibers. The approach combines acidic DES pretreatment with alkaline DES dissolution, significantly improving processing efficiency. The cellulose pulp achieves approximately 85% α-cellulose content while maintaining favorable specific surface area. The DES can be recovered at above 90% for cyclic reuse. Regenerated cellulose fibers (RCF) underwent crystal transition from cellulose I to cellulose II, displaying uniform morphology and enhanced thermal stability. Mechanical testing reveals a breaking strength of 121.5 MPa and elongation of 6.6%. These results demonstrate that this integrated DES approach offers a green and recyclable route for converting non-wood biomass into regenerated cellulose fibers.