Specific lignin precipitation for oligosaccharides recovery from hot water wood extract

Bioresour Technol. 2014:152:31-7. doi: 10.1016/j.biortech.2013.10.113. Epub 2013 Nov 7.

Abstract

Hot water extraction is an important strategy of wood fractionation, by which the hemicelluloses can be separated for value-added products, while the residual solid can still be processed into traditional wood products. In this study, a combined process consisting of specific lignin precipitation and dialysis was proposed to recover hemicellulosic oligosaccharides (OS) from hot water extract (HWE). The results showed that polyaluminium chloride (PAC) precipitation was highly specific to large molecular lignin, leading to 25.1% lignin removal with negligible OS loss through charge neutralization mechanism. The separation was further enhanced by dialysis, reaching 37.6% OS recovery from HWE with remarkable purity of 94.1%. By the proposed process, 56.36 g OS, mainly xylooligosaccharides with two fractions of 5.2 and 0.51 kDa was recovered from one kg dried wood. This process can be envisaged as a great contribution to wood biorefinery.

Keywords: Hot water extraction; Oligosaccharides; Polyaluminium chloride; Specific lignin precipitation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aluminum Hydroxide / pharmacology
  • Chemical Precipitation*
  • Dialysis
  • Hot Temperature*
  • Hydrogen-Ion Concentration / drug effects
  • Lignin / isolation & purification*
  • Oligosaccharides / isolation & purification*
  • Particle Size
  • Populus / drug effects
  • Static Electricity
  • Water / pharmacology*
  • Wood / drug effects*

Substances

  • Oligosaccharides
  • Water
  • aluminum oxychloride
  • Aluminum Hydroxide
  • Lignin