Catalytic Degradation of Acrylonitrile−Butadiene−Styrene into Fuel Oil 1. The Effect of Iron Oxides on the Distribution of Nitrogen-Containing Compounds

The thermal and catalytic degradation of acrylonitrile−butadiene−styrene copolymer (ABS) was performed at 400 °C in static nitrogen atmosphere, by semibatch operation. γ-Fe2O3, an Fe3O4−C composite, and α-FeOOH were used as catalysts, in two contact modes:  either mixed with the polymer or in contact with the volatile degradation products of ABS. All iron oxides decrease the concentration of nitrogen (N) in ABS degradation oil. Reactions in a flow-type reactor with 4-phenylbutyronitrile as model N-containing compound show that α-FeOOH is active at low temperatures (250−300 °C) in converting heavy N-containing compounds into light aliphatic nitriles. XRD analysis proved that during reaction α-FeOOH was transformed into Fe3O4 in several steps, with α-Fe2O3 as intermediary compound.