Research Of Catalytic Oxidation Of NO Over V₂O₅ -WO₃/TiO₂

V₂O₅-WO₃/TiO₂ catalysts were studied for influence of performance of NO catalytic oxidation in this paper. The following researches were carried out: (1)The impacts of loading of active component, V/W molar ratio andcalcination temperature on V₂O₅-WO₃/TiO₂ catalysts were investigated. The microstructure and physical states of the catalysts were characterized at a different calcination temperature by XRD and BET. The results showed that the catalyst which loading of 20% V₂O₅, V/W=1:1, 450℃calcined 5h, the specific surface area, pore volume, pore size are maximum and catalytic activity is the best. The optimum catalyst can reach the oxidation rate 31.2%.(2)It can be seen that NO conversion increased with the enhancement of O₂ concentration at a differert operating conditions; we also found that NO conversion decreased with the rise of NO concentration and GHSV. We can see that the activity of the catalyst at low temperature is better, in the reaction temperature to 120℃higher than the activity of the activity of other reaction temperature and catalyst V₂O₅-WO₃/TiO₂ showed good stability.(3) The reaction kinetic equation was expressed as: r_NO= kY_NO^aY_O2 ^b= 0.4142 exp(1292 / RT) [NO]^0.88 [O₂]^0.33 The effects ofExternal diffusion and internal diffusion on the catalytic oxidation reaction can be neglected, indicating that the catalytic process is mainly affected by the overall reaction rate of chemical kinetics.(4)The main reasons that affect V₂O₅-WO₃/TiO₂ catalytic activity were competitive adsorption of SO₂ and NO and SO₂ on the lead chamber reaction, H₂O and NO competitive adsorption of H₂O on the catalytic activity of the main reason V₂O₅-WO₃/TiO₂; The results showed that H₂O and SO₂ had negative impact on the catalytic activity simultaneously, and the deactivated catalyst can't recovery when H₂O and SO₂ were stopped..It indicated that the inactive reaction is reversible.(5)The FT-IR spectra showed that the sulphate and metal nitrates with Ti formed during catalytic oxidation reaction with SO₂, H₂O in the presence.The catalyst was deactivated gradually above 120℃, but its activity could almost be recovered to the nitial level after heat treatment at 250℃. Therefore we can use the operation mode of twin-bed parallel in which one bed is used for catalytic oxidation reaction and the other for heating regeneration. Such mode can be applied to oxidative absorption NO_x of flue gas effectively.