Effect of Mo loading on 2-naphthaldehyde formation from vapor phase oxidation of 2-methylnaphthalene with V2O5/TiO2 catalysts

High-Performance Metal Oxide-Modified V/TiO2 Catalysts for Selective Oxidation of 2-Methylnaphthalene to 2-Naphthaldehyde: An Experimental and Theoretical Study

“…In comparison with the V-Cu/TiO 2 catalyst, V-Fe/TiO 2 maintains high selectivity only at lower temperatures (<380 °C). The catalytic performance of V-Mo/TiO 2 for the selective oxidation of 2-MN is taken from the literature 19 and shown in Figure 1b,d. Only when the operating temperature is above 380 °C, the V-Mo/TiO 2 catalyst shows a higher 2-MN conversion in comparison with V-Cu/TiO 2 , while the 2-NA selectivity of V-Cu/TiO 2 is much higher than that of V-Mo/ TiO 2 in the temperature range 350−400 °C.…”

“…Among these reactions, it is necessary to (a) use highly purified and expensive reactants, (b) apply corrosion-resistant materials due to the strong acid environment, and (c) deal with a large amount of acid waste liquid after the reaction. Hence, the alternative process consisting of the gas selective oxidation of 2-MN by molecular oxygen is promising from an economic and environmental perspective. − …”

“…The key to improving the catalytic performance in this reaction lies in the development of effective catalysts that can control the oxidation of methyl groups. − ,− It is suggested that the breakage of the C–H bond is the rate-controlling step in the oxidation of methyl of hydrocarbons. It will pass through a fairly large energy barrier to break the C–H bond due to the chemical inertia, and this dehydrogenation process takes a lot of energy input. , In addition, for 2-MN, carbon atoms at positions 1 and 4 in naphthalene rings are also reactive on account of the inductive effect.…”

“…Zhang et al 24,25 had studied the selective oxidation of 2-MN over series V/SiO 2 catalysts and found that the major products are menadione and phthalic anhydride, and 2-NA only accounts for a tiny proportion of the product. Gao et al 19 suggested that doping appropriate molybdenum in the V/TiO 2 catalyst can promote the 2-MN conversion and 2-NA selectivity, while the addition of W inhibits the reaction. The V-Mo/TiO 2 catalyst displays good activity and stability, but the 2-NA selectivity is still low.…”

“…(Reaction conditions: 0.5 g catalysts; GHSV = 10 000 h −1). The catalytic performance of the V-Mo/TiO 2 catalyst was taken from the literature 19.…”