Birch is a standout wood species: Half of the weight of birch outer bark
consists of betulin and fatty acids of suberin. These compounds can replace
pine oil and resin in technochemical products. They can also be used in
pharmaceuticals. VTT is researching and developing the potential for producing
birch bark-based products in Finland and their business opportunities.
At the moment, birch bark is mainly combusted for production of heat and
electricity. At sawmills and pulp plants, birch logs are debarked mechanically
in large drums. Birch bark is thus available in great quantities.
Betulin and suberin fatty acids can also be used in the production of fine
chemicals and paints, glues and other such products commonly made using pine
oil and resin, as well as in the pharmaceutical and cosmetics industries.
About half of the content of birch outer bark consists of betulin and suberin.
The valuable components can be easily recovered from the bark by means of
solvent extraction and NaOH treatment before the remainder is combusted.
Betulin is a water-repellent and pure white terpene compound that is harmless
to health. Its rigid structure and high melting point make it suitable for use
in the production of polymers, resins and coatings, for example. Betulin gives
birch bark its white colour. It also has bioactive characteristics that could
be highly significant in the future. Currently, betulin is utilised
commercially mainly in cosmetics and health foods and supplements.
Suberin is a fatty acid compound that is also harmless to health. Its
water-repellent and lubricating properties make it an appealing industrial raw
material for polymers, resins and lubricants.
Applications range from glues and paints to pharmaceuticals
Betulin and suberin fractions can be used to replace pine oil and resin in
paints, glues, inks and rubber. Even though many studies have been conducted
and few patents granted , no such products are yet on the market due to the
high price and limited availability of betulin and suberin fractions. The
price of raw pine oil has risen substantially in recent years, and will most
likely continue to do so, as the use of pine oil and resin becomes more common
in biodiesel production.
VTT is also researching the use of compounds made from betulin as antibodies
for viruses, protozoa and bacteria as well as in cancer treatment.
Betulin-based substances are a new kind of compound group. In cell culture
experiments carried out at VTT, the most potent betulin compounds were highly
effective at preventing the growth of microbes and cancer cells.
At present, suberin is not commercially available. The price of high-quality
betulin can be as high as several hundred euros per kilo. According to VTT’s
preliminary calculations, the production costs of these compounds could in the
best-case scenario – that is, when the extraction plant is located at a birch
plywood mill – be close to those of fractions produced from raw pine oil.
VTT is currently assessing the production potential of these compounds in
Eastern Finland in association with Savonlinnan yrityspalvelut Oy and local