Hydroxyl-Mediated Non-oxidative Propane Dehydrogenation over VO x /γ-Al2 O3 Catalysts with Improved Stability

Influence of the Porous Structure of V2O5-ZrO2-SiO2 Catalyst on Reaction of Propane Dehydrogenation

A spherically granular, amorphous, mesoporous catalyst was obtained by supporting V2O5 on synthesized by direct sol-gel method of ZrO2-SiO2 hydrogel and was identified by SEM, XRD and N2 adsorption / desorption. It is shown that its hydrothermal and alcohol treatment increases the specific surface, volume and width of pores and leads to an increase in the yield of propylene in the reaction of propane dehydrogenation and decreases the temperature of reaching its high values.

Tailoring Single-Atom Platinum for Selective and Stable Catalysts in Propane Dehydrogenation

Propane dehydrogenation has been a promising method for producing propylene that has the potentials to meet the increasing global demand for propylene. However, owing to the restricted equilibrium conversion caused by the high endothermicity, even the Pt-based catalysts, which exhibit high activity and selectivity, severely suffer significantly from coke formation and/or nanoparticle sintering at realistic reaction temperatures, resulting in a short catalyst lifetime. As a result, few innovative catalysts in terms of catalytic activity, selectivity, and stability, have been produced. In this Review, we focus on the characteristics of single-atom-like Pt sites for PDH and attempt to provide suggestions for developing highly efficient catalysts. First, we briefly describe the fundamental strategies. Following that, the remarkable catalysis is addressed by three different distinct sorts of state-of-the-art single-atom-like Pt catalysts are discussed. Additionally, we present other promising catalyst design approaches that are not based on single-atom-like Pt catalysts, as well as future research challenges in this field.

Investigation of vanadia-alumina catalysts with solid-state NMR spectroscopy and DFT

In this work, isolated surface sites of vanadium oxide on the alumina surface were modeled and compared to experimental data obtained with ⁵¹V Solid-State Nuclear Magnetic Resonance (SSNMR) spectroscopy. The geometry of the centers on the (100), (110), and (111) planes of the spinel structure and (010) monoclinic alumina was modeled using density functional theory (DFT); their ⁵¹V NMR parameters were calculated using the Gauge-Including Projector Augmented Wave (GIPAW) method. The comparison of the simulated theoretical spectra with the experimental ones made it possible to find the sites that are likely present on the surface of real catalysts. The minimum energy pathways of propane oxidative dehydrogenation to propene were calculated for the dioxovanadium site in order to estimate its activity.

High-Density Lewis Acid Sites in Porous Single-Crystalline Monoliths to Enhance Propane Dehydrogenation at Reduced Temperatures

The non-oxidative dehydrogenation of propane to propylene plays an important role in the light-olefin chemical industry. However, the conversion and selectivity remain a fundamental challenge at low temperatures. Here we create and engineer high-density Lewis acid sites at well-defined surfaces in porous single-crystalline Mo₂ N and MoN monoliths to enhance the non-oxidative dehydrogenation of propane to propylene. The top-layer Mo ions with unsaturated Mo-N_1/6 and Mo-N_1/3 coordination structures provide high-density Lewis acid sites at the surface, leading to the effective activation of C-H bonds without the overcracking of C-C bonds during the non-oxidative dehydrogenation of propane. We demonstrate a propane conversion of ≈11 % and a propylene selectivity of ≈95 % with porous single-crystalline Mo₂ N and MoN monoliths at 500 °C.