Effects of Zeolite Type on Integrated Fischer–Tropsch Synthesis and Hydroprocessing

• Published in: Petroleum chemistry 2022-08, Vol.62 (8), p.950-961
• Main Authors: Yakovenko, R. E., Bakun, V. G., Agliullin, M. R., Sulima, S. I., Zubkov, I. N., Pyatikonova, V. V., Bozhenko, E. A., Savost’yanov, A. P.
• Format: Article
• Language: English
• Subjects: Analysis; Catalysts; Chemical synthesis; Chemistry; Chemistry and Materials Science; Cobalt; Fischer-Tropsch process; Fuels; Hydrocarbons; Industrial Chemistry/Chemical Engineering; Molecular sieves; Selectivity; Zeolites
• ISSN: 0965-5441; 1555-6239
• DOI: 10.1134/S0965544122070209

A number of bifunctional composite cobalt-based catalysts were prepared with various types of molecular sieves in the H-form (zeolites ZSM-5, Y, Beta, and Mordernite, and silicoaluminophosphate SAPO-11) as an acid component. The catalytic performance of these catalysts was comparatively assessed in integrated Fischer-Tropsch synthesis of fuels. The catalysts were found to exhibit high activity and high C 5+ selectivity at 2.0 MPa, 240–250°C, and a gas hourly space velocity (WHSV) of 1000 h –1 . With the CO conversion reaching 80.9–93.7%, the productivity was in the range of 146.4 kg/(m 3 cat h). The study further revealed the effects of the crystalline and porous structures of the molecular sieves on the hydrocarbon and fractional compositions of the fuel products and on the selectivity towards branched hydrocarbons. It was shown that catalysts based on HZSM-5 and HBeta zeolites are preferable for high-performance and selective synthesis of fuels. In the presence of the HZSM-5-based catalyst, an effect atypical of Fischer–Tropsch synthesis was observed for the first time: an elevation of the process temperature leads to an enhancement of C 5+ selectivity.