Preparation Of Cu²⁺ Doped Catalyst And Study On Catalytic Deodorization Performance Of Its Synergy With NTP

At present,H₂S waste gas from landfills has been regarded as one of the typical odorous pollutants in China’s air pollutants,which seriously affects people’s work and daily life,and it is urgent to treat it efficiently.In recent years,low temperature plasma synergy with catalysis has become a hot research area.As the catalyst of the carrier,the multiporous material greatly increases the active site of the reaction and can effectively improve the degradation rate.In this paper,Cu²⁺doped porous catalysts were prepared by sol-gel method.Through Br（?）nsted acidic sites generated by Al,Cu²⁺ions were promoted to enter the electrically neutral ordered skeleton with regular order.The addition of Al effectively solved the problem of copper doping.Through BJH and MIP pore size analysis,the catalyst had a multi-pore structure of meso-micropore and macropore.XPS and EDX characterization results confirmed that Cu was doped into the skeleton.SEM,BET,XPS,EDX,NH3-TPD,MIP and other characterization methods were used to investigate the distribution of doped Cu²⁺and the chemical properties of the catalyst.The prepared porous catalyst was combined with a self-made wire-tube double-dielectric barrier discharge reactor to form a synergistic degradation system.The effects of input voltage,gas flow,and H₂S initial concentration on the degradation efficiency were investigated.The yield of ozone（O₃）during the degradation process was measured,and the effect of O₃on H₂S degradation was studied.The degradation effect of internal and external coupling systems was studied by changing the coupling mode.The change of catalyst before and after reaction was analyzed and the mechanism of synergistic catalytic degradation of H₂S by low temperature plasma was discussed.The results showed that the addition of porous catalyst improved the degradation efficiency of H₂S,and it can be completely removed at 35V voltage.Compared with low temperature plasma interaction alone,the residence time of H₂S in discharge gap and the impact probability of highly active particles were increased due to the adsorption property of porous structure of porous materials,and the degradation efficiency of pollutants was improved.On the other hand,the transition metal Cu²⁺facilitated the capture of reactive oxygen species,promoted the reaction between H₂S and reactive oxygen species,and improved the catalytic performance.In different coupling modes,the internal coupling system can intercept H₂S,made it fully contact with the active substance,and improved the discharge efficiency.On the one hand,H₂S was more likely to be bombarded by high-energy electrons.On the other hand,H₂S can fully contact with more active substances,and interact with reactive oxygen species on the surface of the catalyst to promote the fracture of H₂S chemical bonds and improve the degradation efficiency of H₂S.In the internal coupling system,the contact point formed between catalyst particles and reactor wall would produce more filamentous discharge when the electric field increased,which enhanced the discharge process of the whole system.Compared with NTP reaction alone,the output efficiency reached 64.79%at 35V,which promoted the output efficiency of the power supply.Moreover,the active center of the catalyst promoted the generation of more plasma active substances,making the degradation of H₂S more effective.However,external coupling system of high energy electron production was reduced,the discharge space produced the short life of active species unable to act directly on the external surface of the catalyst,only O₃with a long life generated in the discharge space can be captured by the external catalytic system to further decompose O₃into reactive oxygen species,which can only increase the active substances a little and promote the degradation of H₂S.