Hemicellulose is a carbohydrate biopolymer second only to cellulose, which is rich and has a broad application prospect. The limitation of high-value utilization of hemicellulose has been a long-standing challenge due to its complex and diversified structure. The extraction and subsequent modification of hemicellulose from lignocellulosic biomass represent a promising pathway toward this goal. Herein, the extraction processes including physical pretreatment, chemical pretreatment, and combined pretreatment for separating hemicellulose from lign...