| The use of fossil energy emits large amounts of CO2,causing some critical environmental issues such as the greenhouse effect.To control the emissions of CO2,China has proposed the carbon peaking and carbon neutrality goals.Focusing on these goals,the establishment of a sound green low carbon cycle development economic system is on the agenda.As a zero-carbon energy source,the resource disposal of organic solid waste can help to achieve the carbon peaking and carbon neutrality goals.Organic solid waste incineration for power generation can effectively realize the synergistic benefits of pollution reduction and carbon reduction,yet its incineration can generate large amounts of nitrogen oxides(NOx),which are hazardous to the ecological environment and human health.Among numerous NOx removal technologies,selective catalytic reduction(SCR)technology has became the most widely used denitrification technology due to its high removal efficiency,and the core of this technology is the SCR denitrification catalyst.Compared with traditional coal-fired power plants,the flue gas of organic solid waste incineration power generation plants contains more toxic components that can cause the deactivation of SCR denitrification catalysts,which affects the stable operation of SCR catalysts and seriously reduces the catalyst life.Therefore,it is important to develop the SCR denitrification catalysts that are suitable for the complex flue gas environment of organic solid waste incineration power generation plants.In this paper,the deactivation mechanism of commercial V2O5-MoO3/TiO2(VMoTi)catalysts in the typical flue gas environment,which is rich in KCl and PbCl2,was investigated.On this basis,the modified catalysts were developed to resist the synergistic poisoning of KCl and PbCl2.The main results are as follows:Firstly,fresh,KCl,PbCl2 and synergistic poisoning V2O5-MoO3/TiO2 catalysts were prepared by impregnation method to investigate the deactivation effect of VMoTi catalysts under the different flue gas environments.The SCR denitrification catalysts with the synergistic poisoning mechanism of KCl and PbCl2 were elucidated by different physicochemical characterization combined with DFT caculation.The results showed that the specific surface area,surface acidity and redox properties of the catalysts were further reduced after the synergistic poisoning of KCl and PbCl2 compared to that of single KCl and single PbCl2 poisoning.In addition,the interaction of K-Mo and the with the interaction of Pb-V reduced the activity of the active components and weakened the adsorption and activation of NH3.Then,the enhancement of the resistance to KCl and PbCl2 synergistic poisoning of VMoTi catalysts with different loading concentrations of Ce(SO4)2 modification was investigated.The 15 wt%Ce(SO4)2 loading V2O5-MoO3/TiO2 catalyst was observed to have the best resistance to the synergistic poisoning of 2 wt%KCl and PbCl2.Meanwhile,the mechanism of Ce(SO4)2-modified resistance to the synergistic poisoning of KCl and PbCl2 was revealed by a series of characterization techniques combined with DFT caculation.The results showed that the interaction between Ce(SO4)2 and KCl and PbCl2 protected the V and Mo active sites.Meanwhile,the introduced Ce4+/Ce3+redox pair provided a large number of oxygen vacancies for the catalyst,which provided favorable conditions for the formation of chemisorbed oxygen and improved the redox ability of the catalysts.Moreover,the Ce(SO4)2-modified catalyst maintained a high surface acidity despite the synergistic poisoning of KCl and PbCl2 species,which was beneficial to the adsorption of NH3 species and the subsequent SCR process. |
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