Polycyclic Aromatic Hydrocarbons in Birch Wood Slow Pyrolysis Products

The products from slow pyrolysis of birch hardwood are promising to be used for various purposes, in addition to, conventional Charcoal. To evaluate their utilization, knowledge about their polycyclic aromatic hydrocarbons (PAHs) is needed. The content and distribution of the PAHs in the different products were determined in a test run with a typical slow pyrolysis. carbonization retort. The PAH compositions of gases, and distillates including aqueous phases and tars, were followed in terms of time and retort temperature. Also, other compounds in gases and aqueous phases through the test run were analyzed. PAHs were found in the products, but Were mostly concentrated in the tars. Because the results, the PAK contents in the tars has to be Considered. In contrast, very low PAN concentrations were found for the tar-free aqueous phases. Because of low PAH and also low benzene contents the aqueous phases are promising to be utilized in various applications, for example as biodegradable pesticides. Due to high proportions of combustible gases, such as carbon monoxide, methane, and hydrogen, the gases could be unified as a fuel gas for energy. In addition to barbecue charcoal, the charcoal Might have potential to be used as biochar as. a soil: amendment. The PAH results can be exploited when planning the utilization of the products and for registration purpose needed in the commercialization.