Selectively isolated hemicellulose with high whiteness and molecular weight from poplar by sodium perborate-assisted alkali extraction

As one of the three main components of lignocellulose (cellulose, hemicellulose and lignin), the physical and chemical properties of hemicellulose determine the reaction and solubility characteristics of hemicellulose to the commonly used agents for component separation, and the preferential extraction of hemicellulose is an important way to realize the high value utilization of biomass. Herein, an efficient new method of hemicellulose extraction by sodium perborate-assisted potassium hydroxide pretreatment was proposed. The extraction of hemicellulose with high whiteness and molecular mass under lower temperature conditions was achieved. The effects of chemical dosage, temperature and time on the separation efficiency and characteristics of hemicellulose were comprehensively investigated. The results showed that sodium perborate could greatly improve the separation efficiency of hemicellulose. Under the optimal process conditions of 10wt% KOH combined with 3%NaBO 3 at 85 ℃ for 3 h, the removal rate of hemicellulose could reach 83.34% and the recovery rate was 64.50% Meanwhile, the extracted hemicellulose possessed significantly low color value and high molecular (23.35 kDa). The preferential removal of hemicellulose not only provides a raw material guarantee for the high-value utilization of hemicellulose but also facilitates the opening of lignocellulosic cell wall channels, which is conducive to the further processing and utilization of biomass feedstock.