So there is growing interest in researching methods and techniques for recycling these materials. One possible solution studied recently involves mushrooms. Researchers found that wood fungi, which are already known to decompose organic pollutants such as DDT, TNT and PCB, can also break down phenol resins. The researchers created cultures with eleven different types of fungus and observed the most efficient decomposition with white wood mushrooms. Biodegradation of phenol resins is demonstrated by the change in colour of the mushroom as it absorbs the phenol and formaldehyde, the monomers from which the resin is produced. The presence of these substances in the mushrooms was then verified using laboratory techniques (gas chromatography and 13C analyses). It is possible to hypothesise that the phenol and formaldehyde could then be extracted from the mushrooms and used to make new resins, thus providing a perfect example of a closed circuit.
This is undoubtedly an important discovery, which sheds new light on the degradation of phenol resins and could make mushrooms an important factor in large-scale recycling of these resins. On the other hand this is only a first step: more advanced research is needed to better understand the factors which influence the degradation process and above all to translate the process to an industrial scale, in order to demonstrate that it can be applied to mass recycling.
In conclusion, degradation of phenol resins using fungi is certainly an interesting alternative to dumping, and is well worth following up, but its use for recycling of resins is premature and needs further research.
(Hi-Tech Ambiente, Italy, www.pubblindustria.com)