Structural and chemical modifications of typical South African biomasses during torrefaction

Lihle D. Mafu, Hein W.J.P. Neomagus, Raymond C. Everson, Marion Carrier, Christien A. Strydom, John R. Bunt

Research output: Contribution to journalArticlepeer-review


Torrefaction experiments were carried out for three typical South African biomass samples (softwood chips, hardwood chips and sweet sorghum bagasse) to a weight loss of 30wt.%. During torrefaction, moisture, non-structural carbohydrates and hemicelluloses were reduced, resulting in a structurally modified torrefaction product. There was a reduction in the average crystalline diameter (La) (XRD), an increase in the aromatic fraction and a reduction in aliphatics (substituted and unsubstituted) (CPMAS 13C NMR). The decrease in the aliphatic components of the lignocellulosic material under the torrefaction conditions also resulted in a slight ordering of the carbon lattice. The degradation of hemicelluloses and non-structural carbohydrates increased the inclusive surface area of sweet sorghum bagasse, while it did not change significantly for the woody biomasses.

Original languageEnglish
Pages (from-to)192-197
Number of pages6
JournalBioresource Technology
Early online date14 Dec 2015
Publication statusPublished - Feb 2016

Bibliographical note



  • biomass
  • torrefaction
  • XRD


Dive into the research topics of 'Structural and chemical modifications of typical South African biomasses during torrefaction'. Together they form a unique fingerprint.

Cite this