Catalytic Role of Ionic Liquids for Dissolution and Degradation of Biomacromolecules

Abstract

Natural biomacromolecules constitute a diverse feedstock, including carbohydrate-based polysaccharides (cellulose, hemicellulose, starch, agarose, and Konjac glucomannan) together with lignin -extracted mainly from biomass -and other protein based polymers, namely keratin, chitin, chitosan, and silk fibroin. The complex and heterogeneous chemical structure of biomacromolecules makes them difficult to dissolve and disintegrate into simpler molecules for further applications. In this regard, ionic liquids are potential solvents for the dissolution and modification of long chain biopolymers. This provides a promising pretreatment technology and is known to allow adequate extraction of biopolymers from natural sources. This paper highlights the properties of ionic liquids for their use as versatile solvents. This review provides a critical outlook regarding the influence of several process parameters that govern the fractionation of biomacromolecules into their constituent elements and further pretreatment processes. The performance of different types of ionic liquids for processing of biomacromolecules, focusing on their pertinent capability as catalysts to enhance the rate of hydrolysis, also is discussed in this article.

Regenerated Lignocellulose Beads Prepared with Wheat Straw

“…Owing to their negligible vapor pressures and high thermal stability, they can be regarded as green solvents having many potential applications (Wasserscheid and Stark 2014). Some ILs dissolve lignocellulosic materials or their components (cellulose, hemicellulose, and lignin), which greatly promotes the utilization of lignocellulosic resources (Chowdhury et al 2014;Morais et al 2015;Peleteiro et al 2015;Silveira et al 2015). After dissolution in ILs, lignocellulosic materials can be converted into various products, such as furfural (Carvalho et al 2015), cellulosic aerogels , lignocellulosic aerogels (Li et al 2011), and modified regenerated bamboo that removes Cd 2+ and Pb 2+ (Zhong et al 2012).…”

“…The morphology and properties of the obtained beads were characterized. Wheat straw was used as the raw material, and 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), a frequently-used solvent of lignocellulosic material (Chowdhury et al 2014;Badgujar and Bhanage 2015), was selected as the solvent.…”

Development and treatment procedure of arsenic-contaminated water using a new and green chitosan sorbent: kinetic, isotherm, thermodynamic and dynamic studies

“…This model considers that no axial dispersion occurs in the system. Equation 16 shows the linearized equation of this model [39][40][41][42]:…”

“…The model shows that the equilibrium is not instantaneous because the sorption is proportional to the concentration of the sorbate and the residual capacity of the sorbent. The linearized model is presented by [39][40][41][42]:…”

Synthesis of a Novel Allyl-Functionalized Deep Eutectic Solvent to Promote Dissolution of Cellulose

“…However, its utilization as an isolated polymer is hindered by its water-insoluble crystalline structure and highly packed polymeric macromolecules (Gümüşkaya et al 2002;Sathitsuksanoh et al 2013). Dissolution, which prepares for the subsequent hydrolysis, saccharification, catalyzed reaction, etc., is the principal step of cellulose processing (Alvira et al 2010;Gericke et al 2012;Chowdhury et al 2014;Castro et al 2015). Conventional solvents, including sulfuric acid, phosphoric acid, lithium chloride/N, N-dimethylacetamide, sodium hydroxide/urea, and tetrabutylammonium fluoride trihydrate/dimethyl sulfoxide, have shown efficient ability to dissolve cellulose (Boerstoel et al 2001;Nayak et al 2008;Ru et al 2015).…”