Synthesis Of ZrNiAl Derived Complex Metal Oxides Catalytic Oxidation Performances Of SO₂ And Propylene Catalyzed Reduction Of NO

This paper focuses on the research and application of metal oxidation material desulfurization and denitrification,Research on NiAl derived complex metal oxide catalysts used in catalytic oxidation of SO₂ and catalytic reduction of NO.The catalyst was prepared by co precipitation method with urea as precipitant and Ni/Al molar ratio of 3.The Zr was introduced into the carrier as the active component,and a series of physical and chemical properties were tested.The main conclusions are as follows:1.The modification of NiAl hydrotalcite catalyst was carried out,Zr with strong affinity to oxygen was selected as the active component,The results show that the introduction of Zr has a positive effect on the catalytic activity of the catalyst.Results in TPD and In situ FTIR indicate.When the Zr load is 5%,Whether the catalytic oxidation of SO₂,or catalytic reduction of NO,Comparison of other loading catalysts,The catalytic effect of 5%ZrNiAlO is the best;On the one hand,there is a strong interaction between Zr and NiAl,On the other hand,Zr can not only increase the active site and oxygen concentration of the catalyst surface,but also increase the number of L acid on the catalyst surface,Promote more SO₂ and NO adsorption and activation on the catalyst surface.2.In the process of catalytic oxidation of SO₂ by NiAl derived complex metal oxide catalyst,Analysis by in situ FTIR spectroscopy,The results show that SO₂ can produce sulfate and sulfite species on the catalyst surface,These species are adsorbed on the surface of the catalyst on a steady state.In the reaction,SO₂ reacts with the hydroxyl group on the surface of the catalyst to form sulfite.OH-consumption increases the effective use of O₂-.Under the condition of O₂,the catalytic performance of the catalyst is stronger than that of N2.This is because the O₂ in the gas phase is easily adsorbed on the surface of the catalyst to form reactive oxygen species,To provide more active oxygen sites in the catalytic reaction.In addition,NiAlO has the ability of oxidation and reduction,which helps to oxidize SO₂ to sulfite.3.Catalyst in the catalytic reduction of NO,Based on the analysis of in situ FTIR spectra,The participation of 0 changed the way of catalyst surface oxidation to NO.Under anaerobic conditions,The main species on the catalyst surface are nitrate and weakly adsorbed NO and NO₂;Under oxygen rich conditions,The main species are nitrate and nitrite.The deficiency of O reduces the oxygen active sites formed on the catalyst surface,At the same time,the catalytic activity of the catalyst was weakened.In addition,in the selective catalytic reduction of NO by C3H6,Whether the involvement of O has a great influence on the transformation of NO.Under the condition of sufficient oxygen,Bidentate nitrate is an active intermediate in the selective catalytic reduction of NO by C3H6.With the increase of C3H6 throughput,To promote the gradual reduction of bidentate nitrate into mono nitrate.