POLYCYCLIC AROMATIC-HYDROCARBONS IN WASTE DERIVED PYROLYTIC OILS

Waste material in the form of wood waste, municipal solid waste and rice husks was pyrolysed in a gas-purged static batch reactor and a fluidised bed reactor. The condensed pyrolytic oils were analysed for their content of polycyclic aromatic hydrocarbons (PAH). The oils were fractionated into chemical classes using mini-column liquid chromatography followed by analysis using GC/FID and GC/MS for identification and quantitation of PAH. The waste derived oils were found to contain substantial concentrations of PAH, which were formed via secondary Diels-Alder and deoxygenation reactions. The concentrations of PAH were influenced by reactor temperature and residence time. The PAH consisted mainly of naphthalene, fluorene and phenanthrene and their alkylated homologues, but also included some PAH which were of known carcinogenic or mutagenic activity.