Chemical Deodorant Effects of Pyroligneous Liquids from Woody Materials

Pyroligneous liquids from woody materials are a valuable forest resource, although they are a byproduct of charcoal production. Chemical deodorant effects of pyroligneous liquids were investigated to expand their applications. Three pyroligneous liquids, which were made from nara (Quercus serrata Thunb. and/or Quercus crispula Blume), ubamegashi (Quercus phillyraeoides A. Gray) and mosochiku (Phyllostachys pubescens Mazel), were evaluated through deodorization tests. Five chemical compounds, ammonia, trimethylamine, hydrogen sulfide, methyl mercaptan and acetaldehyde, were adopted as sources of offensive odors. All the pyroligneous liquids showed remarkable deodorant effects on ammonia and trimethylamine, which are basic compounds. Pyroligneous liquids from nara and mosochiku had no or few deodorant effects on hydrogen sulfide and methyl mercaptan, while both the sulfur compounds showed a reduction of about 30% through a 24-hour deodorization test using pyroligneous liquid from ubamegashi. It has been clarified that considerable amounts of acetaldehyde were volatilized from all the pyroligneous liquids.