https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:44004 0.15Fe_0.05/fly-ash catalysts have been synthesized by the co-precipitation method using coal fly ash (FA) as the catalyst carrier. The catalyst showed high catalytic activity for low-temperature selective catalytic reduction (LTSCR) of NO with NH3. The catalytic reaction experiments were carried out using a lab-scale fixed-bed reactor. De-NOx experimental results showed the use of optimum weight ratio of Mn/FA and Fe/FA, resulted in high NH3-SCR (selective catalytic reduction) activity with a broad operating temperature range (130–300 °C) under 50000 h−1. Various characterization methods were used to understand the role of the physicochemical structure of the synthesized catalysts on their De-NOx capability. The scanning electron microscopy, physical adsorption-desorption, and X-ray photoelectron spectroscopy showed the interaction among the MnOx, FeOx, and the substrate increased the surface area, the amount of high valence metal state (Mn4+, Mn3+, and Fe3+), and the surface adsorbed oxygen. Hence, redox cycles (Fe3+ + Mn2+ ↔ Mn3+ + Fe2+; Fe2+ + Mn4+ ↔ Mn3+ + Fe3+) were co-promoted over the catalyst. The balance between the adsorption ability of the reactants and the redox ability can promote the excellent NOx conversion ability of the catalyst at low temperatures. Furthermore, NH3/NO temperature-programmed desorption, NH3/NO- thermo gravimetric-mass spectrometry (NH3/NO-TG-MS), and in-situ DRIFTs (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) results showed the Mn0.15Fe0.05/FA has relatively high adsorption capacity and activation capability of reactants (NO, O2, and NH3) at low temperatures. These results also showed that the Langmuir–Hinshelwood (L–H) reaction mechanism is the main reaction mechanism through which NH3-SCR reactions took place. This work is important for synthesizing an efficient and environmentally-friendly catalyst and demonstrates a promising waste-utilization strategy.]]> Wed 05 Oct 2022 15:04:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:28659 Cu⁺ > Cu²⁺. Fe₃O₄ was believed to be the active phase in Fe catalyst. The oxygen and char-supported metal catalysts significantly promoted C/NO reaction, and therefore may lead to a lower operation temperature of NOₓ removal.]]> Sat 24 Mar 2018 07:37:12 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40041 2. The influence of the concentrations of NO and O₂ on the oxidation of NO was investigated. Besides, the changes in the reaction rate with the particle size of the catalysts were investigated to determine the internal diffusion resistance. The surface area and microcrystalline structure of the catalysts were analyzed to investigate the impact of physical structure on SO₂ poisoning in the catalyst. It was observed that Co doping in Mn/TiO₂ had a favorable impact on reducing the effect of SO₂ poisoning during the NO oxidation reaction. On the basis of the kinetic study, it was concluded that the reaction followed the Langmuir−Hinshelwood (L-H) mechanism, where NO and O₂ were adsorbed on the catalyst, forming highly reactive NO⁺ and O⁻, which were then converted into NO₂. The Co doping into the TiO₂ crystal lattice increased the O₂ adsorption, thus accelerating the rate of NO oxidation reaction.]]> Fri 22 Jul 2022 13:14:04 AEST ]]>