2. Since the first utilization of timber as
a structural material, man has
sought to extend the service life of
wood by reducing moisture
sorption.
• Biblical Times: Pitch
• Ancient Greece: Olive oil
• Roman Times: First use of petroleum treatments
3. Within the last century, petroleum
products have dominated the wood
preservation industry’s moisture
resistant treatments
• John Bethell (1804-1867)
• Full-Cell Process
• Creosote
• Pentachlorophenol
4. In the context of this work, water
repellency is the primary mechanism
for increasing wood durability
European researchers are studying many natural
water-repellent treatments
• Linseed Oil
• Sunflower Oil
• Rapeseed Oil
5. • Enviromental Impact- life of the product
within the environment
• Economic Impact- cost structure of the
product and end-user pricing
The wood-products industry must develop
‘environmentally sensitive’
products to satisfy consumer demand and
the increasing regulatory pressure
6. • Improve the moisture resistance of
southern yellow pine
• Impregnate southern yellow pine (pinus
spp.) with wood pyrolysis oil
• Determine differences between high and
low pressure treatment
• Determine the minimum retention levels
necessary for improved moisture resistance
7. Pyrolysis is a process where cellulosic biomass
is heated in an oxygen-free environment:
•Traditional
•Slow heat transfer, long residence time
•High char and low gas production
•Fast
•Fast heat transfer, short residence time
•Low char and high gas production
•Best suited for pyrolysis oil production
14. Research Methods: Water Repellency
Materials:
• Whole bio-oil
• Southern Yellow Pine (1” x 1” cubes)
Methods:
1. Conditioned to a stable moisture content
2. Determine specific gravity
22. • Pyrolysis oil was successfully impregnated into
Southern Yellow Pine using either high or low
pressure methods
• In a vapor environment moisture resistant
benefits to moisture sorption and tangential
expansion plateaued at concentrations of 10%
• In a soak environment, benefits were directly
related to the concentration of pyrolysis oil
• Leachability of the treatment from the substrate
is the main drawback to this treatment option