In situ molten salt derived iron oxide supported platinum catalyst with high catalytic performance for o-xylene elimination.

An in situ molten salt strategy is developed for the convenient preparation of iron oxide-supported platinum catalysts with high performance for o -xylene elimination. The high catalytic performance of the supported platinum catalysts is due to the improvement in redox ability and o -xylene activation. • Supported Pt catalyst is prepared using an in situ molten salt method. • Supported Pt catalyst exhibits high catalytic activity for o -xylene removal. • Pt loading enhances the redox ability of the supported Pt catalyst. • Pt loading improves the adsorption and activation of o -xylene. • Improvement in redox ability and o -xylene activation benefit high activity. Supported noble metal catalysts are highly effective for eliminating volatile organic compounds (VOCs). A catalyst with less noble metal loading is always desirable. Using a mixture of NaNO 3 and NaF as molten salt, Fe(NO 3) 3 and Pt(NH 3) 4 (NO 3) 2 as metal precursors, x Pt/Fe 2 O 3 catalysts (x = 0–0.3 wt%) were fabricated after calcination at 350 °C for 3 h. At space velocity of 40,000 mL/(g h), 0.22 wt% Pt/Fe 2 O 3 showed the best catalytic activity, and o -xylene could be completely oxidized into CO 2 and H 2 O at 225 °C. Furthermore, 0.22 wt% Pt/Fe 2 O 3 exhibited good stability, and high resistance to water vapor, CO 2 , and SO 2. We deduce that the excellent catalytic performance of 0.22 wt% Pt/Fe 2 O 3 was associated with the high dispersion of the Pt species and good low-temperature reducibility. The possible reaction mechanism of o -xylene oxidation over 0.22 wt% Pt/Fe 2 O 3 involved the adsorption of o -xylene molecules, partial decomposition into small organic intermediates (e.g. maleic anhydride and aliphatic carboxylate species), and total oxidation into CO 2 and H 2 O. Due to the high efficiency, good stability, low cost, and convenient preparation, the present catalysts are promising for the practical removal of VOCs. [ABSTRACT FROM AUTHOR]