Fuel fractions obtained in the recycling of plastics

The decomposition of mixtures of polystyrene, polyethylene, and motor oil was studied at 470 - 510°C in a flow-through setup supplied with a fluidized bed reactor and a cascade of receivers. The aim of the work was to determine the role of the fluidized bed in the reactor, in the process of degradation of plastics in the cases where it was only a carrier of heat for the endothermal process of pyrolysis or it was both a carrier of heat and a catalytic bed for the process. The effect of the catalyst granulation and of the method of the organization of work in the reactor on the yield of the process and on the composition of the products obtained, was also studied.

In the cases where Al₂ O₃ of granulation 0.2 mm was used as a fluidized bed catalyst the liquid products of the decomposition of the polymers contained mainly alkyl-aromatic derivatives of styrene, benzene and alkane hydrocarbons. If nano-Al₂ O₃ was used as a catalyst and it was introduced into the reactor with a stream of raw materials, the obtained products were solids, composed mostly of styrene and alkene hydrocarbons.