Application of ionic liquids for effective use of woody biomass

Abstract

Ionic liquids are salts that have melting points around ambient temperature and unique characteristics, such as high solubility, extremely low volatility, incombustibility and low viscosity. Application of ionic liquids in wood processing technology has attracted attention and is expected to promote further use of wood. They are effective as wood-preserving agents to enhance decay-resistance and also improve fire resistance of wood. Ionic liquids have been used as reaction solvents for preparing various cellulose derivatives or composites with other materials. Attempts have been made to use ionic liquids in pretreatments for enzymatic hydrolysis when producing bio-ethanol from cellulose or wood. Ionic liquids also have been shown to be effective for dissolution of cellulose or wood, forming the basis for studies into the separation of cellulose, hemicellulose and lignin from wood. The effective separation of these components is essential for chemical use of wood, and ionic liquid treatment thus has potential as an enabling technique in biorefineries. Moreover, ionic liquids induce depolymerization of solubilized wood polymers, which may be applicable to the production of useful chemicals from wood polymers such as cellulose, hemicellulose and lignin.

Ionic Liquids as Antifungal Agents for Wood Preservation

“…One class of emerging wood preservative candidates could be ionic liquids (ILs). These ionic organic compounds, which have been around since the late 1970s, have been intensively researched in the last decade concerning their solvation ability for lignocellulose, biomass derivatization potential, and multipurpose-additives for wood-based materials (antistatic agents, thermal and radiation stabilizers, plasticizers, and so forth) [ 27 , 28 , 29 , 30 ].…”

On the Anion Exchange of PX3 (X = Cl, Br, I) in Ionic Liquids comprising Halide Anions

“…[1][2][3][4][5][6][7] Owing to their distinctive physical properties, such as a wide temperature range of the liquid phase, high redox and thermal stability, negligible vapor pressure, and tuneable polarity, ILs are discussed as solvents for various fields of applications. They can be used, e.g., in separation techniques, [8][9][10] electrochemistry, [11][12][13][14] catalysis, [15][16][17][18][19][20] organic synthesis, [5,[20][21][22][23] processing of biomass, [24][25][26][27][28] and in the synthesis of inorganic materials. [5,[29][30][31][32][33][34][35] Thus, the replacement of conventional solvents with ILs seems to be feasible and in many cases advantageous.…”

Sustainable Wood Nanotechnologies for Wood Composites Processed by In-Situ Polymerization

“…For example, green polymer grafting approaches were applied to wood fiber and CNF surfaces through surface-initiated ring-opening polymerization of bio-derived lactones ( Lönnberg et al, 2006 ; Herrera et al, 2020 ; Olsén et al, 2020 ). Green delignification treatments for wood substrates were explored such as peracetic acid, ionic liquids, and deep eutectic solvents ( GP-4 , GP-5 , and GP-7 ) ( Miyafuji, 2015 ; Chen Z. et al, 2019 ; Montanari et al, 2020 ). When the purpose of delignification is to remove light-absorbing components, eco-friendly bleaching processes can be employed to remove chromophores while retaining most of the lignin ( Li et al, 2017a ).…”