Kamlet–Taft Parameters of Deep Eutectic Solvents and Their Relationship with Dissolution of Main Lignocellulosic Components

Abstract

Deep eutectic solvents (DESs) have attracted significant interest in dissolving lignocellulosic components. However, revealing the relationship between the solvation properties of DESs and their ability to dissolve lignocellulosic components remains a significant challenge. Herein, 56 DESs were prepared and applied to dissolve lignocellulosic components. This revealed that the Kamlet−Taft parameters (i.e., α, β, and π*) were significantly affected by the structures of DESs. More notably, the correlation between Kamlet−Taft parameters and solubility varied with DESs and lignocellulosic components. Concretely, DESs have greater values of β and β−α (net basicity), are expected to dissolve cellulose efficiently, have greater net basicity, and are favorable to dissolve lignin, and the solubility of xylan was linearly correlated with the β value. These findings provided valuable information and necessary theoretical guidance on designing robust DESs to dissolve lignocellulosic components based on Kamlet−Taft solvatochromic parameters.

Natural Biomass Soups (NBSs): New Green Solvents Replacing Ionic Liquids and Deep Eutectic Solvents for Lithium-Ion Batteries Recovery

“…Another feature of NBSs is their low cost and natural abundance while ILs and DESs are generally expensive and require industrial processes. In addition to LIBs recovery, NBSs could be biomass utilization, gas capture/conversion, material synthesis, catalysis, and electrolytes, just like ILs and DESs. ,,− …”

“…Deep eutectic solvents (DESs) are mixtures of binary or ternary components characterized by a lower melting point than each of their individual constituents . Specifically, DESs should be evaluated by the solid–liquid diagram rather than only the lower melting point. , The intermolecular interaction could be hydrogen bonds or halogen bonds; the components could be either molecules, ionic compounds, or metals. − These distinctive attributes have led to DESs being lauded as the “green solvents of the 21st century” and “designable solvents”. Comparatively, DESs are frequently called IL analogues because both DESs and ILs typically keep a liquid state near room temperature. , As a result, DESs have attracted considerable attention in both scientific research and chemical industry due to their high tunability and extensive range of potential applications. ,− …”

Recent advances in catalytic conversion of lignin to value-added chemicals using ionic liquids and deep eutectic solvents: a critical review

“…20. 148 This knowledge can inform the strategic design of DESs for more efficient lignin processing. The list of all DESs used for catalytic transformation of lignin and its model compounds to chemicals is shown in Table 4.…”

Unravelling photoisomerization dynamics in a metastable-state photoacid

“…In this K-T approach, [29][30][31] any solvent-influenced property of the solute may be correlated using a multiparameter fit to the following equation: P s-s = P 0 s-s + sp* + aa + bb, where P s-s is the measured solventinfluenced property of the solute, P 0 s-s is the numerical value of the chosen solute property in a known reference solvent, or ideally, in the gas phase, p* is the normalized solvent polarity scale, a and b are the solvent acidity and basicity scales, respectively, s, a, and b are the empirical numerical coefficients that characterize the solute. Using the reported p*, a, and b values for neat water (a = 1.17, b = 0.47, p* = 1.14) and glycerol (a = 1.2, b = 0.67, p* = 1.04), [32][33][34] we estimated the corresponding values for different water/glycerol mixtures by calculating the averages of neat glycerol and water values weighted by their relative volumes 34 and converting their weight ratios to volume ratios using water and glycerol densities. Based on the results, we plot the spectral shift shown in Fig.…”