Thermal oxidation of polycyclic aromatic hydrocarbons adsorbed on alumina.

The reevaporation of polycyclic aromatic hydrocarbons (PAH) from secondary alumina (alumina used in a fluidized bed for pot gas cleaning) used in the production of aluminum in aluminum reduction plants has been studied. The secondary alumina contains around 100 ppm of PAH when introduced to the pots. The results of this study indicate that only a minor part of the adsorbed PAH is reevaporated at the pot temperature of 300-400 degrees C and that the use of secondary alumina has little effect on the PAH concentration in the workplace atmosphere of the aluminum reduction plants.