H₂-SCR On A Low Temperature On A Modified MIL-96（Al） MOFs Catalyst

NO_x is considered to be a major pollutant in the atmosphere because of its strong oxidative effect,the contribution to acid rain,photochemical smog,depletion of ozone layer and even global warming.Our society pays more and more attention to environmental problems.In order to meet strict emission laws and regulations,effective NO_x removal techniques are required.MOFs（metal-organic frameworks）are the coordination polymers of metal ions and organic ligands with possess high surface area.Owing to the unique octahedral of aluminum center and strong Al-O bonds,MIL-96（Al）shows excellent thermal stability.We found that almost no record for MOFs applying in denitration progress.Here,MIL-96（Al）is synthesized via a water based route and different contents of Pt particles are directly deposited on the surface of MIL-96 in one step by hydrothermal method to prepare PtxMIL-96（X=0.5,1,5,3,5,represents Pt content）catalysts and applying in H₂-SCR progress.Use BET,EDX,ICP-OES,XRD,FESEM,TEM and XPS to characterize and analyze the catalysts.BET analysis shows the specific surface area will progressively decrease with the increase of Pt content,as the meantime the pore diameter shows no significant change.EDX and ICP-OES analysis show the final Pt content in MIL-96（Al）samples are close to the calculated amount.FESEM and TEM analysis prove that the MIL-96（Al）is effective at dispersing Pt particles evenly and sparsely as it is employed as catalyst support.XPS analysis shows electron transfer has happened between MIL-96（Al）and Pt,which raise the of binding energy metal Pt.The catalyst are sprayed evenly on carbon paper and named as Pt_XMIL-96（Al）/CP,with Pt content of 0.04 wt%,0.12 wt%,0.24 wt%and 0.40 wt%,respectively,and applied in a gas diffusion reactor with snakelike flow field for low temperature H₂-SCR.Test results show that PtxMIL-96（Al）/CP is effective in H₂-SCR.After studying the simulated flue gas composition,found that the existence of oxygen shows inhibitory effect for the catalytic reaction,but its inhibition will gradually decrease with the increase of reaction temperature or hydrogen concentration.The increase of hydrogen concentration can promote the NO removal reaction.And the research of Pt5MIL-96（Al）/CP show it has fantastic stability and shock-resistant capacity.At the same time,the catalysts are sprayed evenly on Ni foam and named as Pt_XMIL-96（Al）/NF,and applied in a gas diffusion reactor with snakelike flow field for low temperature H₂-SCR.Compared the test result of PtxMIL-96（Al）/NF with PtxMIL-96（Al）/CP,found that Ni foam has the capacity of reinforce the hydrogen concentration and reinforce the NO removal efficiency of PtxMIL-96（Al）.