Oxidative decomposition of naphthalene by supported metal catalysts

A fixed-bed reactor was utilized to investigate the activities of six metal catalysts (1% Pt, 1% Pd, 1% Ru, 5% Co, 5% Mo and 5% W on γ-Al₂O₃ support) in decomposing naphthalene, based on the production of carbon dioxide and the disappearance of naphthalene. The Pt and Pd catalysts were found to exhibit higher naphthalene oxidizing activity than other catalysts tested. The Co catalysts, whose activity is similar to that of the Ru catalysts, are promising for naphthalene oxidation. The kinetic results of naphthalene oxidation over 1% Pt/γ-Al₂O₃ catalysts are reported for the first time. A first-order reaction with respect to P_naphthalene was found, while the reaction order with respect to P_O2 decreased with increasing reaction temperatures. A Langmuir–Hinshelwood model was used to describe the observed kinetic behavior. Oxygen adsorption dominates at higher reaction temperatures (>140 °C), and consequently the oxidation of naphthalene over the Pt catalysts appeared to be insensitive to P_O2.