화학공학소재연구정보센터
Catalysis Today, Vol.351, 30-36, 2020
In situ molten salt derived iron oxide supported platinum catalyst with high catalytic performance for o-xylene elimination
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 NaNO3 and NaF as molten salt, Fe (NO3)(3) and Pt(NH3)(4)(NO3)(2) as metal precursors, xPt/Fe2O3 catalysts (x = 0-0.3 wt%) were fabricated after calcination at 350 degrees C for 3 h. At space velocity of 40,000 mL/(g h), 0.22 wt% Pt/Fe2O3 showed the best catalytic activity, and o-xylene could be completely oxidized into CO2 and H2O at 225 degrees C. Furthermore, 0.22 wt% Pt/Fe2O3 exhibited good stability, and high resistance to water vapor, CO2, and SO2. We deduce that the excellent catalytic performance of 0.22 wt% Pt/Fe2O3 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/Fe2O3 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 CO2 and H2O. Due to the high efficiency, good stability, low cost, and convenient preparation, the present catalysts are promising for the practical removal of VOCs.