Study On DeNO_x And Regeneration Characteristics Of Activated Coke Loaded Mn-Cu At Low Temperature SCR

Nitrogen oxides?NO_X?are one of the major pollutants in the environment,causing chemical smog and acid rain,which cause great damage to the ecological environment and human health.Compared with activated carbon,activated coke has the same chemical stability,and has the characteristics of low price,high hardness,and low wear resistance.It also has strong adsorption capacity and is a good choice as a catalyst carrier.However,activated coke still has problems in the deNO_X application of industrial furnaces,such as low deNO_X efficiency,activated coke deactivation mechanism and regeneration technology are not perfect.Therefore,this paper uses MnO_X,CuO and other modified activated coke to find high-activity low-temperature modified activated coke,and studies the adsorption and desorption characteristics of NO_X in the process of low-temperature activated coke desulfurization and deNO_X,and the deNO_X of modified activated coke at low temperature.Regeneration mechanism.In this paper,the activated coke was acid-washed and activated,and the activated coke was loaded with Mn-Cu.The deNO_X activity of the Mn-Cu/AC catalyst with different loading ratios and loadings and calcination temperature was tested.It was found that when the catalyst loading was 8wt.%and Mn:Cu is 7:3 and the calcination temperature is 200°C,the catalyst can obtain the best deNO_X efficiency.The physicochemical properties of the catalyst were studied by SEM,BET,XRD,FTIR and XPS to explore the reaction mechanism.Through the sulfur effect and water influence study on the selected catalyst,it is found that the effect of water vapor on the NO conversion rate of the catalyst is reversible,and when SO₂ and water vapor are simultaneously present,the catalyst will form sulfuric acid on the catalyst surface after adsorbing sulfur.Substances such as salts and sulfites destroy the surface active sites of the catalyst and block the pores of the catalyst,resulting in irreversible deactivation of the catalyst.The catalysts for deactivation of sulfur adsorption were regenerated and activated by thermal regeneration and water washing regeneration.It was found that the washing regeneration method can obtain higher catalytic activity through experiments,and the NO conversion rate after regeneration can still be maintained at a high level.BET,XRD and FTIR characterization showed that the water washing method can better recover the specific surface area and pore volume of the deactivated catalyst,and the oxygen-containing functional groups on the catalyst surface are recovered.The XPS characterization shows that the activity of the catalyst is obviously related to Mn³⁺/Mn⁴⁺,Cu²⁺/Cu⁺,O_?/O_?.Sulfur poisoning will lead to the formation of sulfate on the surface of the catalyst.The activity of the catalyst is reduced by the clogging of sulfate.After regeneration,the activity of the catalyst is improved.It is recovered,and the effect of water washing regeneration is more obvious than heat regeneration.