Direct Thermochemical Liquefaction


Key Points

  • Bio-oil has been considered as a potential wood preservative
  • It can impart both anti-fungal and hydrophobic qualities to wood

Research and patent literature suggest that bio-oils or bio-crudes may have utility as biomass derived wood preservatives.  It has long been known that torrefaction and partial carbonization of wood can prevent microbial growth and moisture uptake during biomass storage.

Tests were performed to evaluate this behavior by Lourençon et al. in which raw wood was dosed with neat and diluted bio-oils at various concentrations.  Wood at their lowest loading of bio-oil, the lowest tested, demonstrated decay resistance improved by 2.6 times versus T. versicolor, and 4.5 times versus G. trabeum fungi.  In tests, their highest loading of bio-oil resulted in extinction of the fungal colony in the first days of test.  This was combined with lower moisture uptake of the treated wood.

Prior patent literature exists suggesting the potential for this concept. 


Lourençon et al., Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation, Journal of Analytical and Applied Pyrolysis, Volume 122, November 2016, Pages 1-6

Freel, B. and Graham, R.G. Ensyn Technologies, Inc., Bio-oil Preservatives, (26 Nov 2002) U.S. patent 6,485,841.