Rapid, selective, and room temperature dissolution of crystalline xylan by a hydrotrope

Atomic Level Interactions and Suprastructural Configuration of Plant Cell Wall Polymers in Dialkylimidazolium Ionic Liquids

“…SAXS profiles of xylan in the two chosen ILs, [EMIM]­[OAc] and [AMIM]­[OAc], showed Q –1 pattern identical to that of cellulose, suggesting that xylan also dispersed as individual polymer chains at the molecular level (Figure A). This is in contrast to a recent study, where a 5% (w/w) xylan solution formed large aggregates in tetraethylammonium hydroxide, indicating that imidazolium-ILs are superior solvents of xylan . A single power-law function with a fixed exponent of −1, representing a rod-like particle, was fitted to our SAXS data in the Q-range of 0.03–0.15 Å –1 (Figure A).…”

“…This is in contrast to a recent study, where a 5% (w/w) xylan solution formed large aggregates in tetraethylammonium hydroxide, indicating that imidazolium-ILs are superior solvents of xylan. 40 A single power-law function with a fixed exponent of −1, representing a rod-like particle, was fitted to our SAXS data in the Q-range of 0.03−0.15 Å −1 (Figure 5A). However, the cross-sectional (shoulder) feature in the high-Q region (Q > 0.2 Å −1 ) was not clearly observable like that of cellulose.…”

Efficient fractionation of pure hemicellulose with high DP from bleached hardwood pulp using LiBr·3H2O and co-production of dissolving pulp

“…It has been known that deacetylated xylan can be obtained by alkali extraction. 61 Since the deacetylated xylan has a linear structure and fewer side chains, it is easy to form crystal structures. The XRD and wide-angle X-ray diffraction (WAXD) patterns of the regenerated hemicellulose in this study are shown in Fig.…”

“…This phenomenon may be due to the tendency of the regenerated hemicellulose to rebuild its crystal structure during regeneration. 61,62 In the regeneration process, the LBTH solvent was highly diluted with ethanol, and the coordinated hydroxyls (with Li + ) of hemicellulose molecular chains could be released and then reassembled, leading to the regeneration of hemicellulose in ethanol. This crystalline structure is different from previous literature reports on crystalline hemicellulose.…”

Cellulose Dissolution, Modification, and the Derived Hydrogel: A Review

“…At the same time, the methylene group on the cation interacts with carbocation (C1) on cellulose through noncovalent forces, forming QAH-cellulose intermediates, thereby breaking intramolecular and intermolecular hydrogen bonding. Such solvents include tetramethylammonium hydroxide (TMAH), [60] tetrabutylammonium hydroxide (TBAH), [61] tetraethylammonium hydroxide (TEAH), [62] tetramethylammoniumhydroxide (TMAH). [63] Compared with alkali/urea, QAH has the advantage of mild conditions and higher efficiency.…”