Experimental Study on In Situ Denitration with Fe₃O₄-Based Catalysts During Coke Combustion

ABSTRACT

Efficient and economical catalysts are pivotal for enhancing burning rate and reducing gas pollutants (e.g. NO and SO₂) during coal combustion. This work evaluated the feasibility of using economical Fe₃O₄-based catalysts to enhance combustion rate and reduce NOx in-situ. Fe₃O₄ alone is found to be effective in both catalytic combustion and NO reduction, and the optimized addition is 6% based on the fuel mass. The enhancement of burning rate is mainly due to the enhanced oxygen transport with Fe₃O₄. Meanwhile, Fe₃O₄ promotes the reduction of NO with CO and coke, while CO₂ and O₂ in the atmosphere have adverse effect on its catalysis activity during combustion. Both CaO and CeO₂ can be used to improve the efficacy of Fe₃O₄, and the optimal addtion was 10% CaO or 2% CeO₂ together with 2% Fe₃O₄ for catalytic coal combustion. On the other hand, for the catalysis on NO reduction, the combination fo 2% Fe₃O₄-4% CaO or 2% Fe₃O₄-4% CeO₂ could minimize the amount of NO emitted during combustion. The enhanced oxygen transfer and electron transfer are responsible for the accelerated combustion and NO reduction for the composite catalysts.

KEYWORDS:

• Catalytic combustion
• NO reduction
• Fe₃O₄
• catalysis activity

Acknowledgments

This work was supported by the Natural Scientific Foundation of China (Grants 22178001 and 21978003) and the Anhui Provincial Natural Science Foundation (2008085ME175). Authors are also appreciative for the financial support from the Provincial Innovative Group for Processing & Clean Utilization of Coal Resource.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was supported by the National Natural Science Foundation of China [22178001, 21978003 and 22178002].