Efficient NO Abatement over Alkali-Resistant Catalysts via Constructing Durable Dimeric VO Species

Area of Science:

• Catalysis
• Environmental Chemistry
• Materials Science

Background:

• Alkali metals in flue gas deactivate catalysts for selective catalytic reduction (SCR) of nitrogen oxides (NOx) by ammonia (NH3).
• Polymeric vanadyl species are crucial for NOx abatement but are susceptible to alkali metal poisoning.
• Developing robust and stable vanadyl species remains a significant challenge.

Purpose of the Study:

• To construct durable, alkali-resistant dimeric vanadium oxide (VOx) active sites for NOx abatement.
• To investigate the effect of alkali metals on the polymerization state of active species.
• To develop improved catalysts for low-temperature NOx removal.

Main Methods:

• Synthesis of TiO2-supported cerium vanadate catalysts with triethylamine assistance.
• Characterization of catalyst structure and active sites.
• Evaluation of catalytic performance for NOx reduction in the presence of alkali metals.

Main Results:

• A more durable dimeric VOx active site was constructed, demonstrating alkali resistance.
• The catalyst maintained stable dimeric VOx species and active sites after alkali metal poisoning.
• Suppressed VOx depolymerization led to increased Brønsted and Lewis acid sites, ensuring efficient NOx reduction.

Conclusions:

• Rational construction of polymerization structures yields robust, alkali-resistant catalysts.
• Dimeric VOx active sites offer a promising strategy for overcoming alkali metal poisoning in SCR catalysts.
• This approach opens avenues for developing effective low-temperature catalysts for NOx abatement.