Furfurylation of Wood - Process, Properties and Commercial Production

The first processes for "furfurylation" of wood (wood modification with furfuryl alcohol) were developed several decades ago. Furfuryl alcohol is a renewable chemical since it is derived from furfural, produced from hydrolysed biomass waste. Over the last decade modernised processes for furfurylation of wood have been developed. These new processes are based on completely new catalytic systems and process additives. The properties of furfurylated wood depend on the retention of grafted/polymerised furfuryl alcohol (PFA) in the wood. At high modification levels (high retention of PFA) the enhancement of a wide variety of properties are achieved: an exceptional hardness increase, exceptional resistance to microbial decay and insect attack, high resistance to chemical degradation, increase in MOR & MOE, and high dimensional stability. At lower modification levels many property enhancements also occur, however to slightly lower extent. Notable are resistance to microbial decay and insect attack, increase in MOR & MOE, and relatively high dimensional stability. Two main processes for production of furfurylated wood have been developed for WPT (Wood Polymer Technology ASA) by the authors - Kebony(TM) Dark ("Black technology") for high modification level and VisorWood(TM) ("Brown technology") for lower modification levels, where the name reflects the colour of the material produced by the process. Commercial production according to the Kebony process has been running since August 2000, mainly for flooring. A small Kebony production plant is now in operation in Lithuania. A larger Kebony/Visor Wood production plant is planned to start up during the first half of 2003 in Porsgrunn, Norway. A plant operating according to the VisorWood process with an annual capacity of 15 000 m(3), is most likely starting up in 2004, Norway. Further commercialisation of the technology will be done through licences issued by WPT.