Influence of the addition of vanadium to Pt/TiO₂ catalyst on the selective catalytic oxidation of NH₃ to N₂

Titanium Silicalite-1 Nanosheet-Supported Platinum for Non-oxidative Ethane Dehydrogenation

“…Figure 7A shows the H 2 -TPR profiles of Pt/M-TS-1 prepared by different Pt loading methods. Two distinct peaks are observed in all three samples, in which the low temperature peak (at ∼373 K) is assigned to the reduction of Pt-oxide (PtO x ) species to metallic Pt 73,74 and the second peak appearing at a high temperature range (above ∼673 K) is associated with the reduction of Pt species that interacts with the M-TS-1 support. For the Pt/M-TS-1 (SE) and Pt/M-TS-1 (WI), the high temperature reduction peaks are both located at ∼723 K, but the peak area is larger in the former sample.…”

“…Specifically, the spent catalyst was prepared by running the NDE reaction over fresh Pt/M-TS-1 (EA) at 873 K and 9000 mL h −1 g −1 space velocity for a TOS of 6 h. After reaction, one portion of the spent catalyst was collected for physicochemical property characterization and the other portion was exposed to a flow air (100 mL min −1 ) at 823 K for 4 h with a ramp rate of 3 K min −1 . As shown in Figure 11A, both the low temperature peak (at ∼373 K) assigned to the reduction of Pt-oxide (PtO x ) species to metallic Pt 73,74 and the high temperature peak (at ∼723 K) associated with the reduction of Pt species bonded onto the M-TS-1 support are observed in spent and regenerated Pt/M-TS-1 (EA). A close comparison among the H 2 -TPR profiles show that the low temperature peak position and intensity are similar among the fresh, spent, and regenerated samples, while the high temperature peak intensity is reduced in the spent catalyst and is restored after catalyst regeneration.…”

Influence of deposition order of dual active components on the NH3-SCO performance of the bimetallic Pt–V system supported on TiO2

“…34 Kim et al modified the Pt 0.1 /TiO 2 catalyst (0.1 wt% Pt) with 2 wt% V for removing 200 ppm NH 3 , and found that the Pt 0.1 /V 2 /TiO 2 catalyst achieved complete NH 3 conversion and ∼80% N 2 selectivity at 250 °C. 35 Although the Pt–V bimetallic catalytic system has presented good NH 3 -SCO performance, there are still challenges in balancing the NH 3 conversion activity and N 2 selectivity, as well as further reducing the dosage of Pt. 34,35 The authors considered that the catalytic performance of the Pt–V bimetallic catalytic system significantly depended on the combination mode of the Pt and V components.…”

“…35 Although the Pt–V bimetallic catalytic system has presented good NH 3 -SCO performance, there are still challenges in balancing the NH 3 conversion activity and N 2 selectivity, as well as further reducing the dosage of Pt. 34,35 The authors considered that the catalytic performance of the Pt–V bimetallic catalytic system significantly depended on the combination mode of the Pt and V components. The optimization of the deposition order of the Pt and V components is expected to further improve the comprehensive performance of the Pt–V bimetallic catalytic system, thus solving the above challenges, but the relevant studies are still scarce.…”

Ammonia Abatement via Selective Oxidation over Electron-Deficient Copper Catalysts

“…A variety of supported catalysts, including noble metals, transition metal oxides, and bimetallic (containing both noble and non-noble metals) catalysts, have been explored for NH 3 -SCO applications. Supported noble metals, such as Pt, − Ag, − Au, and Ru, are highly active at low temperatures, but their application is hindered by the poor selectivity to N 2 , the easy formation of NO x byproducts, and the high cost. Transition metal oxides, despite their relatively lower activities compared with those of noble metals at low temperatures, offer opportunities for highly efficient slip NH 3 abatement thanks to their high N 2 selectivity and low cost. , Among others, Cu-based catalysts are particularly promising because they often demonstrate relatively high activity and excellent N 2 selectivity. − Nevertheless, the temperature achieving complete NH 3 conversion, which was found to be above 240 °C for most of the reported Cu-based catalysts, ,− is higher than that of typical flue gases after NH 3 -SCR treatments and requires additional energy input to achieve in practical applications.…”