Synthesis, characterization and cellulose dissolution capabilities of ammonium-based room temperature ionic liquids (RTILs)

Abstract

Green synthesis of room temperature ionic liquids (RTILs), are presented as friendly and challenging solvents for the effective dissolution of oil palm-lignocellulosic biomass. A series of Bronsted acidic-ionic liquids were prepared by the direct neutralization of diethyl dimethyl ammonium hydroxide with several (economical and environmental friendly) Bronsted acids as RTILs. The structural and physicochemical characterization was performed by applying various techniques as Fourier transform infrared (FT-IR), nuclear magnetic resonance (NMR), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), zeta-nanosizer and dynamic light scattering (DLS) respectively, to state the effect of anion on the extended cellulose dissolution capabilities of the synthesized RTILs under mild conditions. As a polysaccharide solvent, diethyl dimethyl ammonium phosphate (A1P) showed the extreme capability to extract 65 % of cellulose from biomass without any pretreatment for 30 min. The present study could be a significant step toward the synthesis of efficient RTILs and generating upgraded cellulose for Hi-tech engineered composites and energy concerns.

When Functionalization Becomes Useful: Ionic Liquids with a “Sweet” Appended Moiety Demonstrate Drastically Reduced Toxicological Effects

“…Indeed, as stated above, it could contribute to decreasing the IL toxicity, but it also endows the structure with high coordinating ability. By incorporating this feature, some of these ILs have been obtained [41][42][43] and in some cases, they have been applied to create ionic liquid gels and thermochromic systems aimed at environmental preservation. [44][45] With respect to previous reports in literature, [41][42][43] our synthetic approach allowed inserting a gluconic-like residue on the cation structure.…”

Sugar-Based Ionic Liquids: Multifaceted Challenges and Intriguing Potential

“…The above-mentioned strategy, based on the neutralization-metathesis reaction of d -gluconic acid in its linear form, has been widely used [ 17 , 43 , 44 , 45 , 46 ]. This approach uses as a reagent the hydroxide of a suitable organic cation, in turn, obtained by simple anion exchange from a neutral salt, and produces the desired IL and an easy-to-remove byproduct as water [ 17 , 43 , 44 , 45 , 46 ]. Not only could these compounds be used as a bases, but even guanidine was used to obtain a direct acid-base reaction without the formation of any byproduct ( Scheme 7 ) [ 17 ].…”

“…For sugar-derived ionic liquids, only one paper concerning the application in biomass dissolution has been published [ 45 ].…”

Insights into the Properties and Potential Applications of Renewable Carbohydrate-Based Ionic Liquids: A Review

“…Javed et al [ 16 ] used N , N -diethyl- N , N -dimethylammonium gluconate, easily prepared by neutralization of diethyl dimethyl ammonium hydroxide with gluconic acid, to extract cellulose from oil palm lignocellulosic biomass. By using this sugar-derived IL, 52% wt.…”

“…Notably, such systems have been recognized for their applicability as organocatalysts and solvents in ways that take advantage of their chirality [ 9 ]. Currently, broadened perspectives regarding potential IL applications span electrochemistry [ 10 ], energy storage [ 11 , 12 ], anti-bacterial systems [ 13 , 14 ], herbicides [ 15 ], and biomass conversion [ 16 ]. Carbohydrates have also recently been shown to reduce toxicity when incorporated into common imidazolium IL structures, thereby further enhancing their biocompatible character [ 17 ].…”