Mechanical pretreatment improving hemicelluloses removal from cellulosic fibers during cold caustic extraction

Bioresour Technol. 2015 Sep:192:501-6. doi: 10.1016/j.biortech.2015.06.011. Epub 2015 Jun 9.

Abstract

Hemicelluloses removal is a prerequisite for the production of high-quality cellulose (also known as dissolving pulp), and further recovery and utilization of hemicelluloses, which can be considered as a typical Integrated Forest Biorefinery concept. In this paper, a process of combined mechanical refining and cold caustic extraction (CCE), which was applied to a softwood sulfite sample, was investigated. The results showed that the hemicelluloses removal efficiency and selectivity were higher for the combined treatment than that for the CCE alone. The combined treatment can thus decrease the alkali concentration (from 8% to 4%) to achieve a similar hemicelluloses removal. The improved results were due to the fact that the mechanical refining resulted in increases in pore volume and diameter, water retention value (WRV) and specific surface area (SSA), all of which can make positive contributions to the hemicelluloses removal in the subsequent CCE process.

Keywords: Cold caustic extraction; Dissolving pulp; Fiber morphology; Hemicelluloses removal; Mechanical refining.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cellulose / chemistry*
  • Cold Temperature
  • Liquid-Liquid Extraction / methods*
  • Plant Extracts / chemistry*
  • Polysaccharides / chemistry
  • Polysaccharides / isolation & purification*
  • Sodium Hydroxide / chemistry*
  • Stress, Mechanical
  • Wood / chemistry*

Substances

  • Plant Extracts
  • Polysaccharides
  • Sodium Hydroxide
  • hemicellulose
  • Cellulose