Toward development of single-atom ceramic catalysts for selective catalytic reduction of NO with NH3

Alexandre A S Gonçalves; Filip Ciesielczyk; Bogdan Samojeden; Mietek Jaroniec

doi:10.1016/j.jhazmat.2020.123413

Toward development of single-atom ceramic catalysts for selective catalytic reduction of NO with NH₃

J Hazard Mater. 2021 Jan 5:401:123413. doi: 10.1016/j.jhazmat.2020.123413. Epub 2020 Jul 7.

Authors

Alexandre A S Gonçalves¹, Filip Ciesielczyk², Bogdan Samojeden³, Mietek Jaroniec⁴

Affiliations

¹ Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44240, United States.
² Faculty of Chemical Technology, Institute of Chemical Technology and Engineering, Poznan University of Technology, PL-60965 Poznan, Poland.
³ Faculty of Energy and Fuels, AGH University of Science and Technology, PL-30059 Krakow, Poland.
⁴ Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44240, United States. Electronic address: jaroniec@kent.edu.

PMID: 32763703
DOI: 10.1016/j.jhazmat.2020.123413

Abstract

Insertion of transition metal species into crystalline alumina at low temperatures is proposed to achieve the dispersion of these species at atomic level paired with exceptional textural properties. Precisely, MeAl₂O₄/γ-Al₂O₃ (Me = Mn, Fe, Co, Ni, and/or Cu) nanostructured ceramic catalysts were fabricated with ultra large mesopores (16-30 nm), and high specific surface area (180-290 m² g^-1) and pore volume (1.1-1.6 cm³ g^-1). These ceramics were applied as efficient catalysts for the selective catalytic reduction (SCR) of NO with NH₃, and their selectivity was discussed in terms of N₂O formation, an undesirable byproduct. The catalysts containing Fe, Cu, or Mn showed the highest activities, however, within different temperature ranges. Further tuning of the catalytic activity and selectivity was achieved by creating ceramic catalysts with mixed compositions, e.g., CuFe and MnFe. Upon insertion of the transition metal species into crystalline structure of alumina to maximize atom efficiency, the N₂O formation profile did not change significantly for all metal aluminates except MnAl₂O₄, indicating that these catalysts are suitable for SCR and selectively promote the reduction of NO.

Keywords: Ceramic catalyst; Metal aluminates; Nanostructured catalyst; Selective catalytic reduction; Single-atom catalyst.