Effects of copper loading on NH3-SCR and NO oxidation over Cu impregnated CHA zeolite

• Published in: The Korean journal of chemical engineering 2018, 35(1), 214, pp.89-98
• Main Authors: Akter, Nusnin, Chen, Xianyin, Parise, John, Boscoboinik, Jorge Anibal, Kim, Taejin
• Format: Article
• Language: English
• Subjects: Ammonia; Biotechnology; Catalysis; Catalysts; Catalytic activity; Chemical synthesis; Chemistry; Chemistry and Materials Science; Conversion; Copper; Industrial Chemistry/Chemical Engineering; Materials Science; Moisture content; Molecular structure; Nitrogen dioxide; Nitrous oxide; Oxidation; Reaction Engineering; Selective catalytic reduction; Selectivity; 화학공학
• ISSN: 0256-1115; 1975-7220
• DOI: 10.1007/s11814-017-0268-x

Cu/CHA catalysts with various Cu loadings (0.5 wt%–6.0 wt%) were synthesized via incipient wetness impregnation. The catalysts were applied to the selective catalytic reduction (SCR) of NO with NH 3 and NO oxidation reaction. XRD and N 2 adsorption-desorption data showed that CHA structure was maintained with the incorporation of Cu, while specific surface areas decreased with increasing Cu loading. At intermediate Cu loading, 4 wt%, the highest NH 3 -SCR activity was observed with ∼98% N 2 selectivity from 150 °C to 300 °C. Small amounts of water, 2%, slightly increased NO conversion in addition to the remarkable N 2 O and NO 2 reduction at high temperature. Water effects are attributed to the improved Cu ion reducibility and mobility. NO oxidation results provided no relation between NO 2 formation and SCR activity. Physicochemical properties, NO conversion, N 2 selectivity, and activation energy data showed that impregnated samples’ molecular structure and catalytic activity are comparable to the conventional ion-exchanged (IE) samples’ ones.