Kinetics and Mechanism of Catalytic Oxidation of NO in Coal Combustion Flue Gas over Co-Doped Mn–Ti Oxide Catalyst

Abstract

The coprecipitation method was used to prepare Mn/Ti, Mn/Co/Ti, and Co/Ti metal oxide catalysts to oxidize NO with O 2 . The influence of the concentrations of NO and O 2 on the oxidation of NO was investigated. Besides, the changes in the reaction rate with the particle size of the catalysts were investigated to determine the internal diffusion resistance. The surface area and microcrystalline structure of the catalysts were analyzed to investigate the impact of physical structure on SO 2 poisoning in the catalyst. It was observed that Co doping in Mn/TiO 2 had a favorable impact on reducing the effect of SO 2 poisoning during the NO oxidation reaction. On the basis of the kinetic study, it was concluded that the reaction followed the Langmuir−Hinshelwood (L-H) mechanism, where NO and O 2 were adsorbed on the catalyst, forming highly reactive NO + and O − , which were then converted into NO 2 . The Co doping into the TiO 2 crystal lattice increased the O 2 adsorption, thus accelerating the rate of NO oxidation reaction.

Review and Perspectives of Enhancement in the Catalytic Stability for the Complete Combustion of CO, CH4, and Volatile Organic Compounds

“…The traditional catalysts might be prematurely aged and inactivated in the complex industrial gas atmosphere (including SO 2 , CO 2 , H 2 O, and so on). 19,20 Therefore, it is very important to design suitable catalysts that can deeply oxidize the pollutants and simultaneously keep stable efficiency under industrial conditions. 21 In this manuscript, we summarize the latest related progress on the stability enhancement for the catalytic removal of CO, CH 4 , and VOCs in terms of the long-term durability, resistance to sinter, and tolerance for multi-impurities (Table 1).…”

Novel Co3(1–x)Fe3xV2O8 Nanoparticles as Highly Active and Noble-Metal-Free Electrocatalysts for Oxygen Evolution Reaction

“…The original electronic structures of the catalysts may be changed by metal doping so as to produce better catalytic properties. − In this perspective, the Fe-doping can improve the OER activity dramatically . Qiu et al reported that the Fe-CoOOH/G nanohybrids acted as a catalyst for OER.…”

Advances in De-NOx Methods and Catalysts for Direct Catalytic Decomposition of NO: A Review

“…In current studies, some scholars have tried to load some other catalyst components (Ce-and Mn-based metal oxides) on the surface of the solid adsorbent to take advantage of the excellent pore structure for catalytic reduction or catalytic oxidation reactions here to remove NO. 35,36 Wet de-NO x refers to the direct absorption of NO with liquid absorbents, mainly including water, dilute nitric acid, alkaline solutions, complexing absorbents, etc. The absorption principles and conditions of each absorbent are various from one to another, resulting in significant differences in the application range.…”

“…This method requires a very large amount of adsorbent but with a limited efficiency, and regeneration of the adsorbent is difficult, with it gradually being phased out in practical industrial applications. In current studies, some scholars have tried to load some other catalyst components (Ce- and Mn-based metal oxides) on the surface of the solid adsorbent to take advantage of the excellent pore structure for catalytic reduction or catalytic oxidation reactions here to remove NO. , …”