Lignocellulosic feedstock materials are the most abundant renewable bioresource material available on earth. It is primarily composed of cellulose, hemicellulose, and lignin, which are strongly associated with each other. Pretreatment processes are mainly involved in effective separation of these complex interlinked fractions and increase the accessibility of each individual component, thereby becoming an essential step in a broad range of applications particularly for biomass valorization. However, a major hurdle is the removal of sturdy and rugged lignin component which is highly resistant to solubilization and is also a major inhibitor for hydrolysis of cellulose and hemicellulose. Moreover, other factors such as lignin content, crystalline, and rigid nature of cellulose, production of post-pretreatment inhibitory products and size of feed stock particle limit the digestibility of lignocellulosic biomass. This has led to extensive research in the development of various pretreatment processes. The major pretreatment methods include physical, chemical, and biological approaches. The selection of pretreatment process depends exclusively on the application. As compared to the conventional single pretreatment process, integrated processes combining two or more pretreatment techniques is beneficial in reducing the number of process operational steps besides minimizing the production of undesirable inhibitors. However, an extensive research is still required for the development of new and more efficient pretreatment processes for lignocellulosic feedstocks yielding promising results.

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木质纤维素原料的不同预处理方法的最新进展：综述。

木质纤维素原料是地球上最丰富的可再生生物资源。它主要由彼此紧密结合的纤维素，半纤维素和木质素组成。预处理过程主要涉及有效地分离这些复杂的相互连接的馏分，并增加每个单独组分的可及性，从而成为广泛应用中必不可少的步骤，尤其是用于生物质增值。然而，主要的障碍是去除坚固且坚固的木质素组分，该组分对溶解具有高度抵抗力，并且也是纤维素和半纤维素水解的主要抑制剂。此外，还有其他因素，例如木质素含量，纤维素的结晶性和刚性，预处理后抑制产物的生产和原料颗粒的大小限制了木质纤维素生物质的消化率。这导致了对各种预处理方法的开发的广泛研究。主要的预处理方法包括物理，化学和生物方法。预处理过程的选择仅取决于应用。与常规的单一预处理工艺相比，结合了两种或多种预处理技术的集成工艺，除了减少了不希望的抑制剂的产生之外，还有利于减少工艺操作步骤的数量。然而，仍需要进行广泛的研究以开发新的和更有效的木质纤维素原料预处理方法，以产生可喜的结果。