An In-Depth Review of Sustainable and Environmentally Friendly Pretreatment Techniques for Cellulose Extraction from Lignocellulosic Biomass and Their Uses

Abstract

Lignocellulosic biomass (LCB), primarily composed of cellulose, hemicellulose, and lignin, represents a valuable renewable resource. Among these components, cellulose is the most abundant biodegradable polymer, with significant industrial potential. However, its efficient isolation remains a major challenge due to its strong association with hemicellulose and lignin within the complex LCB structure. Effective pretreatment strategies are essential to overcome these structural barriers and facilitate cellulose extraction. Conventional pretreatment methods, while effective, often rely on harsh chemicals, elevated temperatures, and high energy inputs, leading to increased costs, low yields, and the formation of fermentation inhibitors, which hinder sustainable biomass utilization. In response to these limitations, environmentally friendly pretreatment approaches have been developed to enhance cellulose separation while minimizing ecological and economic drawbacks. These green methods prioritize efficient delignification, reduced solvent consumption, lower environmental impact, and alignment with sustainable technological advancements. This review explores the application of eco-friendly pretreatment techniques for cellulose isolation from diverse lignocellulosic biomass sources. It further highlights the role of cellulose as a crucial feedstock in the bioeconomy, emphasizing its versatility across various industrial sectors. By advancing sustainable cellulose extraction methods, this research contributes to the broader goal of developing environmentally responsible and economically viable biorefinery processes.