Strategies for regeneration of Pt-alloy catalysts supported on silica for propane dehydrogenation

Reactant-Induced Structural Evolution of Pt Catalysts Confined in Zeolite

“…This effect can be attributed to the interconversion between PtO x and Pt­(CO) x because the diffusion of Pt­(CO) x along the zeolite channels is more difficult than PtO x due to its larger molecule size . Considering the widely employed calcination treatments for regenerating Pt-based catalysts in industrial processes, the presence of an appropriate amount of CO in the oxidative atmosphere (usually air or diluted air) may facilitate to achieve a uniform redispersion of Pt species on the solid carrier …”

“… 28 Considering the widely employed calcination treatments for regenerating Pt-based catalysts in industrial processes, the presence of an appropriate amount of CO in the oxidative atmosphere (usually air or diluted air) may facilitate to achieve a uniform redispersion of Pt species on the solid carrier. 37 …”

“…28 Considering the widely employed calcination treatments for regenerating Pt-based catalysts in industrial processes, the presence of an appropriate amount of CO in the oxidative atmosphere (usually air or diluted air) may facilitate to achieve a uniform redispersion of Pt species on the solid carrier. 37 The results of X-ray absorption near edge spectroscopy (XANES) measurements indicate that the chemical states of Pt species in both Pt-MFI-450-1/16 and Pt-MFI-650-1/16 are close to the PtO 2 reference (Figure 4a). The extended X-ray adsorption fine structure (EXAFS) spectra show that both firstshell Pt−O and Pt−Pt bonds are present in the two samples (Figure 4b).…”

Valence-to-core X-ray emission spectroscopy to resolve the size-dependent valence electronic structure of Pt nanoparticles

“…40 As the energy of the orbitals increases, Pt forms stronger bonds with adsorbates, making it more difficult for species to desorb, which leads to the formation of deeply dehydrogenated species. 14,15,60 Just as nanoparticle size can impact selectivity, it can also affect the rate of reaction by more than an order of magnitude. 20 VtC-XES can also potentially be used in tandem with DFT calculations as experimental validation for computationallydetermined heats of formation; consequently, VtC-XES can help refine calculations to be more accurate and reliable.…”

Self-Organization and Nitrogen Incorporation in Diamond-Like Carbon Microstructures Synthesized by Nonthermal Plasma

“…The development of carbon-neutral technologies for point-source conversion of gaseous alkanes (e.g., biogas and shale gas) to energy-dense products and green hydrogen has received considerable attention in recent years. − Nonthermal plasma stimulation has emerged as a promising solution owing to its ease of coupling with renewable sources of electrical energy combined with its unique ability to reform natural gas at ambient conditions through inelastic collisions with high-energy electrons . In a typical setup, an annular dielectric barrier discharge (DBD) plasma is combined with an appropriate catalyst in either a one- or two-stage process, resulting in enhancements to both the overall activity and product selectivity. − However, plasma-driven C–H and C–C bond scission in light alkanes leads to the uncontrolled formation of coke, which negatively affects the performance of both the catalyst and the plasma and presents a major barrier to commercial implementation. , Thus, achieving an advanced understanding of carbon deposition in plasma reactors and developing strategies to mitigate this issue are critical steps toward the realization of an industrial plasma-catalytic process for light alkane valorization.…”