Ethanol: A Promising Green Solvent for the Deconstruction of Lignocellulose

Abstract

Growing energy demand, environmental impact, energy security issues, and rural economic development have encouraged the development of sustainable renewable fuels. Nonfood lignocellulosic biomass is a suitable source for sustainable energy because the biomass feedstocks are low cost, abundant, and carbon neutral. Recent thermochemical conversion studies are frequently directed at converting biomass into high-quality liquid fuel precursors or chemicals in a single step. Supercritical ethanol has been selected as a promising solvent medium to deconstruct lignocellulosic biomass because ethanol has extraordinary solubility towards lignocellulosic biomass and can be resourced from cellulosic ethanol facilities. This review provides a critical insight into both catalytic and noncatalytic strategies of lignocellulose deconstruction. In this context, the supercritical ethanol deconstruction pathways are thoroughly reviewed; GC-MS, 1D and 2D NMR spectroscopy, and elemental analysis strategies towards liquid biomass deconstruction products are also critically presented. This review aims to provide readers a broad and accurate roadmap of novel biomass to biofuel conversion techniques.

Supercritical Fluids: A Promising Technique for Biomass Pretreatment and Fractionation

“…Lignin fractionation and depolymerization under different strategies, including the use of supercritical fluids, was a theme reviewed by Gillet et al (2017). Also, a review on both catalytic and non-catalytic lignocellulose deconstruction in ethanol, together with a critical revision on the application of analytical techniques (GC-MS, 1D, and 2D NMR spectroscopy, and elemental analysis), was published by Tekin et al (2018). Liu et al (2019) reported an extensive review on biomass utilization with green technologies, including microwave and ultrasonic irradiation, ionic liquids, deep eutectic solvents, electric field processes, and supercritical fluids, among other approaches.…”

Rapid Depolymerization of Decrystallized Cellulose to Soluble Products via Ethanolysis under Mild Conditions

“…From a sustainability perspective, ethanol is an especially attractive reactant and solvent as it is inexpensive, generally non‐toxic, and already produced at a commercial scale from renewable feeds . From a process standpoint, the heat capacity of ethanol is much less than water, thereby reducing heat duties and potentially offsetting energy consumed by ball milling or other decrystallization methods .…”

Study of Organosolv Lignins by Methods of FTIR and NMR Spectroscopy

“…органосольвентных лигнинов). Органосольвентные методы делигнификации имеют ряд преимуществ по сравнению с традиционными технологиями делигнификации [3][4][5]. Они обеспечивают утилизацию всех основных компонентов биомассы, исключают использование токсичных серу-и хлорсодержащих делигнифицирующих агентов, наносящих ущерб окружающей среде.…”