Achieving multiple pollutants control via SCR process: efficacy of VMT catalyst.

Area of Science:

• Environmental Chemistry
• Catalysis Science
• Chemical Engineering

Background:

• Industrial sintering processes release complex pollutant mixtures, including sulfur oxides (SOx), nitrogen oxides (NO), volatile organic compounds (VOCs), and dioxins (PCDD/Fs).
• Simultaneous removal of multiple pollutants is crucial for cost-effective and space-efficient air pollution control upgrades.

Purpose of the Study:

• To evaluate the simultaneous removal efficiency of NO, PCDD/Fs, and toluene using commercial V₂O₅-MoO₃/TiO₂ (VMT) selective catalytic reduction (SCR) catalysts.
• To assess the impact of catalyst composition (MoO₃, V₂O₅, SiO₂, WO₃) and flue gas components (H₂O_(g), SO₂) on catalyst performance and stability.

Main Methods:

• Testing three VMT catalysts (Cat-1, Cat-2, Cat-3) with varying compositions under simulated flue gas conditions at 220 °C.
• Evaluating pollutant removal efficiencies for NO, PCDD/Fs, and toluene.
• Assessing catalyst resistance to poisoning and stability in the presence of H₂O_(g) and SO₂.

Main Results:

• Cat-1, with the highest MoO₃ content, achieved the best overall performance: 93.1% PCDD/Fs, 83.3% NO, and 84.6% toluene removal.
• Cat-2, incorporating SiO₂ and WO₃, showed superior NO and PCDD/Fs removal under H₂O_(g) and SO₂ exposure.
• Cat-3, with the highest V₂O₅ content, demonstrated the highest NO conversion in the absence of co-pollutants and was least affected by them.

Conclusions:

• VMT catalysts are effective for simultaneous multipollutant control in industrial emissions.
• Catalyst composition significantly influences performance and resistance to poisoning by SO₂ and H₂O.
• These VMT catalysts show considerable potential for industrial air pollution control applications.