The strong promotion effects of alkali/alkaline earth metals are frequently reported for heterogeneous catalytic processes such as propane dehydrogenation (PDH), but their functioning principles remain elusive. This paper describes the effect of the addition of calcium (Ca) on reducing the deactivation rate of platinum-tin (Pt-Sn) catalyzed PDH from 0.04 h to 0.0098 h at 873 K under a WHSV of 16.5 h of propane. The Pt-Sn-Ca catalyst shows a high propylene selectivity of >96% with a propylene production rate of 41 mol (g h) and ∼1% activity loss after regeneration. The combination of characterization and DFT simulations reveals that Ca acts as a structural promoter favoring the transition of Sn in the parent catalyst to Sn during reduction, and the latter is an electron donor that increases the electron density of Pt. This greatly suppresses coke formation from deep dehydrogenation. Moreover, it was found that Ca promotes the formation of a highly reactive and sintering-resistant sub-nano Pt-Sn alloy with a diameter of approximately 0.8 nm. These lead to high activity and selectivity for the Pt-Sn-Ca catalyst for PDH.
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http://dx.doi.org/10.1039/d3sc04310j | DOI Listing |
RSC Adv
January 2025
State Key Laboratory of Solidification Processing, Center for Nano Energy Materials, School of Materials Science and Engineering, Northwestern Polytechnical University (NPU), Shaanxi Joint Laboratory of Graphene Xi'an 710072 China
The oxidative dehydrogenation of propane with CO (CO-ODP) is a green industrial process for producing propene. Cerium oxide-supported platinum-based (Pt/CeO) catalysts exhibit remarkable reactivity toward propane and CO due to the unique delicate balance of C-H and C[double bond, length as m-dash]O bond activation. However, the simultaneous activation and cleavage of C-H, C-C, and C-O bonds on Pt/CeO-based catalysts may substantially impede the selective activation of C-H bonds during the CO-ODP process.
View Article and Find Full Text PDFSmall
January 2025
Department of Chemistry and Life Science, Yokohama National University, Yokohama, 240-8501, Japan.
Hydrogen spillover, particularly when involving "interparticle" hydrogen spillover, offers a unique opportunity to enhance catalytic efficiency by remote activation of surface acidity. Building on this concept, this study aims to investigate physically mixed alumina-supported platinum nanoparticles (Pt/AlO) and zirconia-supported tungsten oxide (WO/ZrO) in promoting the direct synthesis of cumene from benzene and propane at 300 °C. The reaction with Pt/AlO alone afforded propylene as the only product, indicating the successive reaction route of Pt-catalyzed dehydrogenation of propane, followed by acid-catalyzed alkylation.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory for Catalytic Conversion of Carbon Resources, School of Chemistry, Dalian University of Technology, Dalian 116024, China.
Metal-free boron-based materials exhibit remarkable performance in oxidative dehydrogenation of propane (ODHP). Rational design of boron-based catalysts requires a systematic understanding of the underlying mechanisms to constitute a knowledge base. This work provides a comprehensive view of the reaction mechanism of the boron-based ODH reaction and discusses the key features of the reaction systems, including the inhibition of deep oxidation, high olefin selectivity, and the role of water in the ODHP reaction.
View Article and Find Full Text PDFAdv Mater
January 2025
Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
The direct dehydrogenation of alkanes to olefins under mild conditions is challenging due to the inert nature of alkyl C─H bonds. Herein, an efficient photocatalytic system is developed for propane direct dehydrogenation (PDH) to propylene, consisting of ≈1.30 nm sized PtO clusters immobilized on a layered double hydroxide -derived ZnO/AlO support (LD-Pt).
View Article and Find Full Text PDFChemSusChem
January 2025
Key Laboratory of Luminescence and Optical Information Technology, School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, 100044, P. R. China.
The eco-friendly features and desirable catalytic activities of Fe-based catalysts make them highly promising for propane dehydrogenation (PDH). However, simultaneously improving their stability and activity remains a challenge. Here, we present a strategy to address these issues synergistically by anchoring single-atom Fe-Cl sites in Al vacancies of AlO.
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