Ga(Nb,Ta)SiBEA zeolites prepared by two-step postsynthesis method: acid–base characteristics and catalytic performance in the dehydrogenation of propane to propylene with CO2

• Published in: Journal of porous materials 2021-10, Vol.28 (5), p.1511-1522
• Main Authors: Orlyk, S. M., Kantserova, M. R., Chedryk, V. I., Kyriienko, P. I., Balakin, D. Y., Millot, Y., Dzwigaj, S.
• Format: Article
• Language: English
• Subjects: Ammonia; Carbon dioxide; Catalysis; Catalysts; Characterization and Evaluation of Materials; Chemical Sciences; Chemistry; Chemistry and Materials Science; Dehydrogenation; Fourier transforms; Infrared spectroscopy; Lewis acid; Magnetic properties; Niobium; NMR spectroscopy; Photoelectrons; Physical Chemistry; Propane; Propylene; Selectivity; Tantalum; X ray photoelectron spectroscopy; Zeolites
• ISSN: 1380-2224; 1573-4854
• DOI: 10.1007/s10934-021-01099-9

Ga(Ta,Nb)SiBEA zeolites with Ta(V), Nb(V) and Ga(III)-single sites were prepared by two-step post-synthesis preparation procedure as evidenced by X-ray Diffraction, Fourier Transform Infrared Spectroscopy (FT–IR), 71 Ga Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy and X-ray Photoelectron Spectroscopy. The acid–base properties of the zeolite catalysts were studied by Temperature-Programmed Desorption of NH 3 and CO 2 with mass-spectrometry control and FT–IR spectroscopy of adsorbed pyridine. The catalytic performance of the Ga(Ta,Nb)SiBEA was tested in the process of oxidative dehydrogenation of propane to propylene with CO 2 . For Ga 4.0 SiBEA zeolite catalyst the propane conversion of 57.5% and propene selectivity of 64–73% at 873 K was achieved. For Ga 1.0 -, Ga 2.0 Ta 2.0 - and Ga 2.0 Nb 2.0 SiBEA catalysts a higher propylene selectivity of 70–77% was reached. The key role of weak and medium strength Lewis acid sites related to the presence of well dispersed framework Ga(III) was determined for the target process.