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Transition metal catalysts can significantly enhance the pyrolytic remediation of soils contaminated with polycyclic aromatic hydrocarbons (PAHs). Significantly higher pyrene removal efficiency was observed after the pyrolytic treatment of Fe-enriched bentonite (1.8% wt ion-exchanged content) relative to natural bentonite or soil (i.e., 93% vs 48% and 4%) at the unprecedentedly low temperature of 150 °C with only 15 min treatment time. DFT calculations showed that bentonite surfaces with Fe³⁺ or Cu²⁺ adsorb pyrene stronger than surfaces with Zn²⁺ or Na⁺. Enhanced pyrene adsorption results from increased charge transfer from its aromatic π-bonds to the cation site, which destabilizes pyrene allowing for faster degradation at lower temperatures. UV–Vis and GC–MS analyses revealed pyrene decomposition products in extracts of samples treated at 150 °C, including small aromatic compounds. As the pyrolysis …