One-Pot Deconstruction and Conversion of Lignocellulose Into Reducing Sugars by Pyridinium-Based Ionic Liquid–Metal Salt System

Abstract

Constantly decreasing fossil resources and exceeding energy demands are the most alarming concerns nowadays. The only way out is to develop efficient, safe, and economical biomass processing protocols that can lead toward biofuels and fine chemicals. This research is one of such consequences involving the deconstruction and conversion of wheat straw carbohydrate constituents into reducing sugars via one-pot reaction promoted by Lewis acidic pyridinium-based ionic liquids (PyILs) mixed with different metal salts (MCl). Various parameters such as the type of metal salt, loading amount of metal salt, time, temperature, particle size of biomass, and water content which affect the deconstruction of wheat straw have been evaluated and optimized. Among the studied ionic liquid (IL) and metal salt systems, the best results were obtained with [BMPy] + CoCl − 3. The dinitrosalicylic acid (DNS) assay was used to determine the percentage of total reducing sugars (TRS) generated during treatment of wheat straw. The deconstructed wheat straw was characterized with various analytical tools, that is, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray powder diffraction (XRD) analyses. The IL-metal salt system was recycled for subsequent treatment of wheat straw. Statistical parameters were calculated from analysis of variance (ANOVA) at the 0.05 level of confidence.

Ionic Liquids Mediated One‐Pot Synthesis of Second Generation 5‐Ethoxymethylfurfural (5‐EMF); A Potent Biofuel Candidate

“…[28] This chloroaluminate tends to deconstruct the lignocellulose into its chief components and simultaneously converts its cellulosic part into monomeric glucose units. [5] Another important task of this chloroaluminate is the mutarotation of stable six-membered glucoside into five-membered furanoside, that is then dehydrated easily to afford an important platform intermediate '5-hydroxymethylfurfural (5-HMF)' having dual functionalities; an aromatic aldehyde and an aliphatic alcohol. [29] Alcoholic functionality of this motif is then etherified by SN 2 mechanism; a good leaving group is formed first by protonation caused by protic acid and then substitution of ethoxy group takes place (Figure 1).…”

“…The most explored gasoline type biofuel derived from this renewable biomass is bioethanol. [5,6] Although it reduces the carbon dioxide emissions, but the downsides for this fuel are its low boiling point, water miscibility and low energy content (6.1 kWhL À 1 ) as compared to 8.8 kWhL À 1 of gasoline. [7,8] In addition, burning ethanol mixtures in car engines causes corrosion, poor engine cold-start performance, production of toxic acetaldehyde [9] and photochemical smog.…”

Evaluating the potential of a novel hardwood biomass using a superbase ionic liquid

“…9d shows the more ruptured structure of biomass exhibiting a conglomerate structure. 36,64 This rough surface of regenerated biomass reveals the removal of lignin and a decrease in the crystallinity of biomass as a result of deep penetration of [TMG][HSO 4 ] at higher temperatures (140 C) as well as longer durations (four hours).…”

Rhododendron and Japanese Knotweed: invasive species as innovative crops for second generation biofuels for the ionoSolv process

“…23,[26][27][28][29][30] The 'one pot process' uses biocompatible ionic liquids such as ethanolamine acetate. [32][33][34][35] The biomass is pretreated and the slurry can be saccharied with no pH adjustment. 36 Finally, the fractionation process selectively dissolves lignin and hemicellulose, leaving a cellulose pulp, which can be washed and further utilised; and a lignin stream.…”