1. Acid Strength Controlled Reaction Pathways for the Catalytic Cracking of 1-Pentene to Propene over ZSM-5
- Author
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Hui Fan, Yue M. Liu, Da W. Zhang, Ming Y. He, Shu F. Zhao, and Long F. Lin
- Subjects
chemistry.chemical_classification ,General Chemistry ,Fluid catalytic cracking ,Photochemistry ,Medicinal chemistry ,Catalysis ,Propene ,Carbenium ion ,chemistry.chemical_compound ,Acid strength ,chemistry ,Pentene ,ZSM-5 ,Selectivity - Abstract
The influence of acid strength was evaluated toward the selectivity to propene on conversion of 1-pentene. For the catalytic cracking of 1-pentene, the main reaction pathways and the molar ratio of propene to ethene (P/E ratio) were controlled by acid strength with the appropriate amount of total acid sites. The results showed that the P/E ratio increased with decreasing amounts of strong acid sites, since the activation energies of individual reaction pathways were influenced by acid strength to a different extent. Strong acid sites could promote pathway I′ (C52– → C22– + C32–) and pathway II′-1 (C62– → C22– + C42–), while weak acid sites preferred pathway II′ (2C52– → C10+ → C42– + C62–) and pathway II′-2 (C62– → 2C32–), since pathways II′ and II′-2 underwent some energetically favorable routes (tertiary–secondary, secondary–secondary) of carbenium ion intermediates. By manipulation of the acid strength distribution on ZSM-5, the P/E ratio and selectivity of propene could be significantly improved, sugg...
- Published
- 2015