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

Abstract

Carbohydrate-derived ionic liquids have been explored as bio-alternatives to conventional ionic liquids for over a decade. Since their discovery, significant progress has been made regarding synthetic methods, understanding their environmental effect, and developing perspectives on their potential applications. This review discusses the relationships between the structural properties of carbohydrate ionic liquids and their thermal, toxicological, and biodegradability characteristics in terms of guiding future designs of sugar-rich systems for targeted applications. The synthetic strategies related to carbohydrate-based ionic liquids, the most recent relevant advances, and several perspectives for possible applications spanning catalysis, biomedicine, ecology, biomass, and energy conversion are presented herein.

Bioderived Ionic Liquids and Salts with Various Cyano Anions as Precursors for Doped Carbon Materials

“…The new ionic systems showed carbohydrate-like, supercooled thermal behavior; once melted, they did not undergo a reversible crystallization, but showed a glass transition, as shown in repetitive heating and cooling experiments conducted with DSC (Figure S3). [33], the latter had higher thermal stability, which is a general trend for imidazolium-based ILs with various anions [1].…”

“…Therefore, the IL with the [TCB] anion had the highest stability when compared to the carbohydrate-derived ILs reported in the literature, except for the bis(trifluoromethanesulfonyl)imide [NTf 2 ] [ 29 , 30 ] and trifluoromethanesulfonate [OTf] [ 31 ] anions. On the other hand, comparing the thermal properties of the investigated carbohydrate-based ILs to their 1-ethyl-3-methylimidazolium analogs ([C 2 mim][DCA], [C 2 mim][SCN], [C 2 mim][TCM]) [ 32 ] and 1- n -butyl-2,3-dimethylimidazolium analog ([C 4 mmi][TCB]) [ 33 ], the latter had higher thermal stability, which is a general trend for imidazolium-based ILs with various anions [ 1 ].…”

“…In addition to the continuous search for useful biomass feedstock and ecofriendly processes suitable for its derivatization, products such as bio-derived solvents, additives, and functional materials are also of special interest. In this regard, bio-derived ionic liquids (ILs) [ 1 , 2 , 3 ] that can serve as solvents for the biomass dissolution desirable in the closed-loop biorefinery concept [ 4 ], as solvents for ionothermal biomass upgrading into functional carbon materials, or as carbon precursors themselves [ 5 , 6 , 7 ] can be useful sustainable chemicals.…”

Heterogeneous Catalysis with the Participation of Ionic Liquids

“…Along with the quest for new alternative methods of the synthesis of ionic liquids with the employment of biodegradable or renewable raw materials, the development of biocatalysis based on ionic liquids began. Increasingly more interesting publications have appeared on this subject [27,30,[50][51][52].…”

“…Currently, there has a common trend to obtain heterogenized systems that combine advantages of homogeneous catalysis (high activity) and heterogeneous catalysis (easiness of isolation, possibility of employing fixed bed reactors), which makes the catalytic process more cost-effective. are frequently employed as precursors of cations, whereas carboxylates of fatty acids, levulinates, and lactates are precursors of anions [24][25][26][27][28][29][30]. Moreover, studies are conducted on the properties of solvents and their effect on the environment and health safety, which enables their conscious and safe use [31].…”