Study On Solid Acid Catalyst For Removing Trace Olefins From Aromatics

In the process of producing BTX,it is important to remove olefins from aromatics when considering production quality and safety of following units.Traditional clay catalysts cannot behave well both in environment-friendly and efficiency,while Zr-solid aicd catalysts can.The properties of Zr-solid acid catalysts are high activity and green which attract many researchers.Firstly,this paper starts from ZrO2 nH2O for preparing Zr-solid acid catalysts(I-ZrOH).The pre-conditions and immersing ratio of H2SO4 of I-ZrOH were investigated for optimal catalytic property.These show the conclusison that non-air pre-conditions were positive for the activity of catlysts and the immersing ratio of H2SO4 were not change the activity of catalysts.Mental oxidations were added into ZrO2 nH2O for modifying the surface acidity of I-ZrOH,which indicated that Al2O3 addition can improve the amount of weak Lewis acidic sites,the conversion of olefins and rigidity of catalysts.In comparsion of solvent-free(S-ZrOH)and immersion method for Zr-solid aicd catalysts,the Lewis acidic sites on the surface of S-ZrOH generate in orders,weak one first,then the strong one,with the increasing of S coverage on the surface.This found also shows the fact that weak Lewis acidic sites can improve the activity of catalysts and strong Lewis acidic sites can weaken the acitivity.And the optimal S-ZrOH was S/Zr=1:3 in the ingredients.In addition,ZrOCl2 8H2O is another raw material for Zr-solid acid catalyst(S-ZrO2).In the research of Zr resouces,ZrO2·nH2O was more suitable for solvent-free method than ZrOCl2 8H2O.VIII mental oxidations were added into S-ZrO2 for enhancing the properties of catalysts.The research indicated that the addition can improve the fraction of S6+ on the surface of S-ZrO2,which is in relationship with weak Lewis acidic sites and activity of catalysts.Ni2O3 turned out to be the most efficient additions for S-ZrO2.