Zeolite-based wood glues shown to absorb pollutants off-gassed from particleboard
By Ben Coxworth
January 14, 2011
It has been estimated that up to 85 percent of all wood materials (such as particleboard or plywood) contain adhesives that in turn contain formaldehyde, and the World Health Organization has classified formaldehyde as a carcinogen. Unfortunately, it’s not enough to simply avoid eating those wood products – even the fumes given off by formaldehyde have been shown to pose a health hazard. Many people turn to keeping spider plants in their homes or offices, as they help neutralize airborne toxins, but now help could be coming from another source. German researchers have discovered that by adding special minerals to wood adhesives, those adhesives themselves can help clean the air.
The research was conducted at Fraunhofer’s Institute for Wood Research and Institute for Silicate Research. The scientists found that modified zeolites, a type of aluminosilicate, were able to act as a kind of “molecular sieve.” This is because they have a porous structure, combined with a very large inner surface – formaldehyde molecules easily find their way in, and then adhere to that inner surface, so they can’t get out.
The best results were obtained specifically from synthetic zeolite Y, after it was modified and improved with amino groups.
“We noticed a 70 percent boost in the adsorption rate after we added formaldehyde to the processed material in our measuring chambers and then we put five percent by weight of the zeolite powder directly into our sample particleboards made of spruce roundwood,” explained Fraunhofer’s Dr. Jan Gunschera. “The result was that formaldehyde emissions from the board dropped 40 percent – both short-term and long-term tests of one month confirm these findings. In other words, the air in living spaces should be measurably improved. Our tests indicate that this technology can even reduce indoor air pollutant levels.”
The properties of the wood did not appear to be affected by the addition of the zeolites. The researchers are now also looking into adding the minerals to furniture and ceiling panels, to further remove formaldehyde and other pollutants from indoor air.