Ionic Liquids in Biomass Processing

Abstract

Ionic liquids have been studied for their special solvent properties in a wide range of processes, including reactions involving carbohydrates such as cellulose and glucose. Biomass is a widely available and renewable resource that is likely to become an economically viable source of starting materials for chemical and fuel production, especially with the price of petroleum set to increase as supplies are diminished. Biopolymers such as cellulose, hemicellulose and lignin may be converted to useful products, either by direct functionalisation of the polymers or depolymerisation to monomers, followed by microbial or chemical conversion to useful chemicals. Major barriers to the effective conversion of biomass currently include the high crystallinity of cellulose, high reactivity of carbohydrates and lignin, insolubility of cellulose in conventional solvents, as well as heterogeneity in the native lignocellulosic materials and in lignin itself. This combination of factors often results in highly heterogeneous depolymerisation products, which make efficient separation difficult. Thus the extraction, depolymerisation and conversion of biopolymers will require novel reaction systems in order to be both economically attractive and environmentally benign. The solubility of biopolymers in ionic liquids is a major advantage of their use, allowing homogeneous reaction conditions, and this has stimulated a growing research effort in this field. This review examines current research involving the use of ionic liquids in biomass reactions, with perspectives on how it relates to green chemistry, economic viability, and conventional biomass processes.

Cleaving the βO4 Bonds of Lignin Model Compounds in an Acidic Ionic Liquid, 1‐H‐3‐Methylimidazolium Chloride: An Optional Strategy for the Degradation of Lignin

“…[13,14] Ionic liquids (ILs) have attracted much attention as a medium for biomass conversion, primarily in the conversion of carbohydrates. [15][16][17] However, few studies report on the reactivity of lignin in ILs. Recently, ILs have been found to be a direct wood pulp solvent capable of solubilizing lignocelluloses.…”

Investigation of Mechanical Properties and Morphology of Multi-Walled Carbon Nanotubes Reinforced Cellulose Acetate Fibers

“…However, the supply of fossil sources is decreasing day by day. The disposal of plastic waste from synthetic polymers is increasing which causes environmental pollution [1]. The environmental impacts include the massive rise in sea levels, increases in carbon dioxide, extreme weather conditions and widespread extinction of animals and plants.…”

Dissolution and Structure Change of Bagasse Cellulose in Zinc Chloride Solution

“…Because of climate change, dwindling fossil fuel resources, and increasing environmental pollution, the development of renewable resources has attracted increasing attention (Pacala and Socolow 2004;Ragauskas et al 2006;Tan and MacFarlane 2010). Bagasse is a typical agricultural waste that is derived from sugar cane and consists of the fibrous residue that remains after crushing to remove sugar from sugar cane stalks.…”