Both softwood (southern yellow pine) and hardwood (red oak) can be completely dissolved in the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C 2 mim]OAc) after mild grinding. Complete dissolution was achieved by heating the sample in an oil bath, although wood dissolution can be accelerated by microwave pulses or ultrasound irradiation. It has been shown that [C 2 mim]OAc is a better solvent for wood than 1-butyl-3-methylimidazolium chloride ([C 4 mim]Cl) and that variables such as type of wood, initial wood load, particle size, etc. affect dissolution and dissolution rates; for example, red oak dissolves better and faster than southern yellow pine. Carbohydrate-free lignin and cellulose-rich materials can be obtained by using the proper reconstitution solvents (e.g., acetone/water 1 : 1 v/v) and approximately 26.1% and 34.9% reductions of lignin content in the reconstituted cellulose-rich materials (from pine and oak, respectively) have been achieved in one dissolution/reconstitution cycle. The regenerated cellulose-rich materials and lignin fractions were characterized and compared with the original wood samples and biopolymer standards. For pine, 59% of the holocellulose (i.e., the sum of cellulose and hemicellulose) in the original wood can be recovered in the cellulose-rich reconstituted material; whereas 31% and 38% of the original lignin is recovered, respectively, as carbohydrate-free lignin and as carbohydrate-bonded lignin in the cellulose-rich material.

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A well-known polyoxometalate, [PV₂Mo₁₀O₄₀]⁵⁻, in both acidic (acidic POM, H₅[PV₂Mo₁₀O₄₀]) and ionic liquid-compatible form ([C₂mim]POM, [1-ethyl-3-methylimidazolium]₄H[PV₂Mo₁₀O₄₀]), has been studied as a catalyst for the dissolution and delignification of wood in the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([C(2) mim]OAc). Differences were observed with variables such as the form of POM, POM loading, and reaction conditions. Generally, the addition of POM leads to a faster dissolution, a lower lignin content in the recovered cellulose-rich materials (isolated pulp), and a lower isolated yield of lignin due to its oxidation. Acidic POM decreases the lignin content of the pulp without compromising the yield of the pulp. [C₂mim]POM in the IL facilitates greater delignification (lower lignin content in pulp) than the IL with acidic POM; however, the overall pulp yield is also lower indicating some degradation of the carbohydrates. The POM can be recovered with [C₂mim]OAc after evaporation of the reconstitution solvent (e.g., acetone/water) and can be reused, albeit with some loss of POM and loss of POM activity under the current conditions.

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Composite fibers were prepared by homogeneous dispersion of nanomagnetite (NM) in the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim]OAc) using ultrasonication followed by dissolution of microcrystalline cellulose at 90°C and dry-jet wet spinning into a water coagulation bath. The processing method with specific successive steps regarding the addition of the components has a large influence on the quality of dispersion and thus the mechanical properties of the fibers. A nanomagnetite load of up to 0.75% (mass ratio expressed in percent of nanomagnetite to cellulose) in the cellulose matrix results in significantly improved mechanical properties of the fibers, while at loads higher than 1% NM, the ultimate stress and modulus of the fibers are lower because of the formation of large agglomerates that create defects within the fibers. Fibers with uniform diameter and better reproducibility of mechanical properties can be produced utilizing high-performance equipment for fiber processing.