Abstract
Nitrogen oxide(NOx)is one of the most critical contaminants in the air,and the control of NOx emis-sion from diesel vehicles is very important.Cu-based small-pore zeolites have already been applied for NOx abatement on diesel vehicles.Among the small-pore zeolites,Cu-SSZ-50 catalysts with good NH3-SCR catalytic activity were believed to have potential for application.In this study,a one-pot synthesis method for Cu-SSZ-50 catalysts was developed for the first time,using the co-templates of Cu-TEPA and 2,6-dimethyl-N-methylpyridinium hydroxide.In this synthesis method,Cu-SSZ-50 with various Cu con-tents can be obtained by adjusting the amount of Cu-TEPA without the need for a further after-treatment process.The addition of Cu-TEPA affected the framework atoms and Cu species,and a lower Si/Al ra-tio and more SCR active Cu species were obtained.The synthesized catalyst with a Cu/Al ratio of 0.40 exhibited over 90％NOx conversion between 200 ℃ and 450 ℃ for the selective catalytic reduction of NOx with NH3(NH3-SCR).Meanwhile,over 80％NOx conversion could be obtained from 250 ℃ to 450 ℃ after hydrothermal aging at 750 ℃ for 16 h.In addition,both L-H and E-R mechanisms were proven to exist for the one-pot-synthesized Cu-SSZ-50 by in situ DRIFTS experiments.The simple synthesis proce-dure,excellent catalytic activity and hydrothermal stability brighten the prospects for the application of Cu-SSZ-50.
基金项目
国家自然科学基金(52200136)
国家自然科学基金(52225004)
国家自然科学基金(51978640)
Science and Technology Innovation"2025"major program in Ningbo(2020Z103)
NETL
NSTL
万方数据