Reduction of emissions from thermally modified timber (TMT) through treatment with ammonia

Abstract

Thermally modified timber (TMT) emits a high amount of aldehydes (furfural, formaldehyde) and volatile organic acids (formic and acetic acids). The release of aldehydes and acids, as assessed by the flask-method (EN 717-3), can be reduced significantly by ammonia fumigation. The emission of formaldehyde is attenuated by more than 90%. Emission of furfuraldehyde decreased in most cases by more than 70%. The pH-value of TMT increased due to ammonia fumigation above the neutral point indicating buffering of the volatile acids.