Glycerin/NaOH Aqueous Solution as a Green Solvent System for Dissolution of Cellulose

Abstract

Dissolving cellulose in water-based green solvent systems is highly desired for further industrial applications. The green solvent glycerin—which contains hydrogen-bonding acceptors—was used together with NaOH and water to dissolve cellulose. This mixed aqueous solution of NaOH and glycerin was employed as the new green solvent system for three celluloses with different degree of polymerization. FTIR (Fourier-transform infrared), XRD (X-ray diffractometer) and TGA (thermogravimetric analysis) were used to characterize the difference between cellulose before and after regenerated by HCl. A UbbeloHde viscometer was used to measure the molecule weight of three different kinds of cellulose with the polymerization degree of 550, 600 and 1120. This solvent system is useful to dissolve cellulose with averaged molecule weight up to 2.08 × 105 g/mol.

The Effect of Cellulose Crystalline Structure Modification on Glucose Production from Chemical-Composition-Controlled Biomass

“…In the case of AS, the maximal intensity of the crystalline region at 22.7 • (I 002 ) and the (101) lattice plane at around 15 • was obvious (Figure 2a,d). This means that the crystalline and amorphous regions were distinguished in the cellulose fibril [2]. These diffractograms were very similar to the feedstock's diffractogram (not presented in this paper), which corresponded to the results of the crystallinity index in Table 1.…”

“…Crystallinity is a unique characteristic of cellulose that has an approximately a 5 µm long chain without substitution in the side groups [1]. Crystalline regions have substantial inter-and intramolecular hydrogen bonds [2]. This structure does not allow for facile decomposition into monomer glucose due to strong hydrophobic and low-reactivity properties [3].…”

“…For the reaction, the typical range of sodium hydroxide concentration is from 1% to 25% based on the weight of the solution with approximately 60 min of reaction time [20]. In addition, other types of alkali reagents were subjected to evaluate the cellulose swelling efficiency depending on the concentration [2].…”

The bidirectional regulation mechanism of NMMO concentration change on cellulose dissolution and regeneration

“…(Li et al 2021). In recent years, the research of cellulose e cient solvent system has attracted wide attention, and a series of excellent solvent systems have been developed, such as Nmethylmorpholine-N-oxide (NMMO) (Zhang et al 2022), lithium chloride / N, N-dimethylacetamide (Lao et al 2020), ionic liquid (Xue et al 2022), inorganic molten salt hydrate (Sen et al 2013), alkali / urea or alkali / thiourea aqueous solution (Li et al 2020). Among the many solvents that dissolve cellulose, NMMO aqueous solution has attracted much attention due to its simplicity, low cost, low toxicity, environmental protection, and easy recovery (Zhao et al 2007).…”

Cellulose (Nano)Composites

“…CNC was also used as a crosslinker in a poly(acrylic acid-co-acrylamide) multi-responsive composite hydrogel for the controlled release of dyes and drugs [9]. Other methods of expanding the application of NC include more appropriate and green solvent systems for cellulose, the use of biobased plasticizers and toughening agents in NC nanocomposites, or the use of molecular dynamics simulations for the prediction of the compatibility and mechanical properties of cellulose blends [10][11][12].…”