Acid-Catalyzed Hydrolysis of Lignocellulosic Biomass in Ionic Liquids for Ethanol Production: Opportunities & Challenges

Abstract

Lignocellulosic biomass (LB) is potentially a relatively inexpensive and abundant feedstock for ethanol production. One of the most challenging steps during the lignocellulosic ethanol production is to convert the carbohydrates in LB to the fermentable reducing sugars (FRS) in an economically viable and environmentally friendly way. The acidcatalyzed hydrolysis of LB in ionic liquids (ILs) has provided a promising technical tool to improve upon the traditional FRS production process. Compared to the conventional FRS production process from LB via the acid or enzymatic hydrolysis method, it has many advantages, such as a simplified process, mild reaction conditions, low acid consumption, and low equipment investment. However, there are still some technical challenges that need to be solved regarding its use at an industrial scale, for example, improving its reaction selectivity, developing effective methods to separate the FRS and ILs, and alleviating the negative effect of the remaining ILs in FRS on subsequent ethanol fermentation. This editorial will give a brief discussion about opportunities and challenges of the acid catalyzed hydrolysis of LB in ILs for ethanol production.

Use of plants to clean polluted air: A potentially effective and low-cost phytoremediation technology

“…Pollutants, including carbon monoxide, SOx, NOx, VOCs, and particulates with toxic metals, can cause dozens of diseases and threaten human health (Burns et al 2020). Many efforts have been made to prevent air pollution (Kelly and Zhu 2016;Zhu et al 2016;Zeng et al 2019). One route to reducing the harm of air pollution to human health is to reduce the emission of air pollutants.…”

Factors Governing the Pretreatment Process of Lignocellulosic Biomass in an Acidic Pyrrolidonium Ionic Liquid

“…Lignocelluloses are primarily composed of cellulose, hemicelluloses, and lignin. Cellulose is a large linear polymer consisting of glucose units that are linked by 1,4-β-D-glycosidic bonds (Zhu et al 2015). Hemicelluloses are a group of polysaccharides that includes xylose, mannose, and arabinose.…”

Microcalorimetric Investigation of the Effect of the Ionic Liquid 1-Butyl-3-Methylimidazolium Chloride on the Fermentation of Saccharomyces cerevisiae AY93161 for Lignocellulosic Ethanol Production

“…Lignocellulosic biomass is the most abundant and renewable natural resource in the world. It has the potential to serve as a renewable feed-stock to chemical commodity and production of fuel, particularly bio-ethanol [2]. Production of ethanol generally consists of two sub-processes: conversion of carbohydrates in lignocellulosic biomass to fermentable sugars and fermentation of the obtained sugars to ethanol.…”

“…Production of ethanol generally consists of two sub-processes: conversion of carbohydrates in lignocellulosic biomass to fermentable sugars and fermentation of the obtained sugars to ethanol. Because of the complex structure of lignin and hemicellulose and cellulose in lignocellulosic biomass, preparation of fermentable sugars is often a challenging work during lignocellulosic ethanol production [2]. Use of ionic liquids has provided a new technical tool to convert the carbohydrates in lignocellulosic biomass to fermentable sugars for ethanol production [3].…”