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To help elucidate the oxychlorination redispersion reaction mechanism, the surface species formed on the surface of γ-Al₂O₃ was characterized by X-ray absorption spectroscopy (XAS). The efficacy of redispersion was assessed by the Pt–Pt coordination number (CN_Pt–Pt) of redispersed, and then reduced samples. A nearly fully redispersed complex (Pt_rd52) was prepared by treating a sintered model Pt/γ-Al₂O₃ catalyst at 520 °C, Air/EDC (ethylene dichloride) of 30, and WHSV (Weight Hourly Space Velocity) of 0.07 h^−1 for 16 h. For investigating temperature effects, samples treated at 460 (Pt_rd46) and 560 °C (Pt_rd56) were also prepared for comparison. It was found that, while an octahedral resembling Pt(O_s)_3–4(O–Cl)_2–3 (O_s represents support oxygen or hydroxyl oxygen) complex was formed on γ-Al₂O₃ of Pt_rd52, less O–Cl ligands were formed on the redispersed complexes, Pt_rd46 and Pt_rd56. A negative correlation of CN_Pt–Pt with CN_Pt–Cl* (Cl* represents the Cl atom in O–Cl ligand) for these three samples further suggested that the formation of Pt–O–Cl played a key role in the redispersion process. Pt–O–Cl could be formed in the reaction of reactive Cl⋅ and PtO₂. At an operation temperature of lower-than-optimal temperatures of 520 °C, less Cl₂ dissociation and less O–Cl ligands were formed. On the other hand, higher temperatures may facilitate Cl₂ dissociation, but reduce the equilibrium conversion of HCl to Cl₂, leading to increased HCl reaction with Pt (PtO₂) clusters to form Pt–Cl (Cl is the atom bonded directly to Pt), and decreased formation of Pt–O–Cl.