Chemical Liquid Deposition (CLD)-Modified Fe-ZSM-5 for Enhanced Activity and Resistance to C₃H₆ Poisoning in Selective Catalytic Reduction with NH₃ (NH₃-SCR)

Abstract

Hydrocarbon fouling can deactivate the catalyst in the selective catalytic reduction (SCR) with NH3 of NO. We use a simple chemical liquid deposition technique to dope a shell layer of SiO2. The results show that it acts as a protective layer against C3H6 while providing abundant Lewis acid sites. which compensate for the relatively less Fe-active sites and therefore contribute to higher overall SCR activities and better resistance to C3H6 poisoning. Moreover, the C3H6 has been found to have promotional effects on SCR at a lower temperature (150 °C), because of the additional SCR reaction with C3H6.

Optimizing the Acid Properties of the HZSM-5 Catalyst for Increasing the p-Xylene Yield in 1-Hexene Aromatization

“…In contrast to other A8 molecules (0.68 nm), PX has a smaller kinetic diameter (0.58 nm), which is more favorable for diffusion in the micropores of HZSM-5 (0.53 × 0.56 and 0.51 × 0.55 nm 2 ). Therefore, it is necessary to utilize the pore selectivity of the catalyst better by prohibiting the EBA of the catalyst. ,, CLD is an effective method for modifying the amount of EBA in the catalysts. − Tetra­ethoxysilane (TEOS) exists only on the surface of HZSM-5 when used as a liquid deposition solution because its kinetic diameter is larger than the microporous pore diameter of HZSM-5. − Xu et al used TEOS as a liquid deposition solution for the CLD treatment of Ga/HZSM-5 to passivate the EBA and found that the silylated catalyst markedly enhanced the aromatic selectivity by inhibiting the alkane cracking occurring on the outer surface in the propane aromatization reaction. Cheng et al reduced the amount of EBA in HZSM-5 by CLD treatment and discovered that the catalyst had higher BTX selectivity because of the inhibition of the alkylation reaction of BTX in the STA reaction after the SiO 2 deposition on the surface.…”