Enhancement of separation selectivity of hemicellulose from bamboo using freeze-thaw-assisted p-toluenesulfonic acid treatment at low acid concentration and high temperature

Bioresour Technol. 2022 Nov:363:127879. doi: 10.1016/j.biortech.2022.127879. Epub 2022 Sep 1.

Abstract

The cellulose-rich residual solids are obtained with p-toluenesulfonic acid (p-TsOH) treatment. However, better fractionation of hemicellulose and separation is difficult to obtain during treatment. This study aims at investigating the separation selectivity of bamboo hemicellulose using freeze-thaw-assisted p-TsOH (F/p-TsOH) treatment. The desired separation effect was achieved at freezing temperature -40 °C, freezing time 20 h, p-TsOH concentration 3.0 %, treatment temperature 130 °C and time 80 min. 93.26 % hemicellulose separation was found, which was 32.88 % higher than that of conventional p-TsOH treatment. Furthermore, the separation yield of lignin decreased significantly from 69.29 % to 13.98 %. The distinct lignin characteristic absorption peaks were found, while that of hemicellulose was difficult to observe. The fiber crystallinity index increased from 50.42 to 56.55 %. Furthermore, greater selectivity for hemicellulose separation was achieved. The results provide a new research thinking for efficient fractionation of lignocellulosic biomass by organic acid treatment.

Keywords: Bamboo; Freeze-thawing; Hemicellulose; P-toluenesulfonic acid treatment; Separation.

MeSH terms

  • Acids
  • Benzenesulfonates
  • Cellulose*
  • Freezing
  • Lignin*
  • Polysaccharides
  • Temperature

Substances

  • Acids
  • Benzenesulfonates
  • Polysaccharides
  • hemicellulose
  • Cellulose
  • Lignin
  • 4-toluenesulfonic acid