Abstract
Two series of supports and catalysts were prepared exchanging β zeolite with alkali or alkali-earth cations. The influence of the exchanged cation (M=Na, K, Rb, Cs, Mg, Ba) on the catalytic behaviour of Pt/Mβ catalyst inn-heptane reactions was studied. Platinum was introduced into the supports by ionic exchange. The supports and Pt catalysts were chemical and structurally characterized by different techniques (AA, ICP, XRD, ammonia TPD, cyclohexane adsorption, H2-TPR, etc.). The acidity and adsorption capacity decrease as the cation size increases. In the case of alkali cations, the catalytic activity of the support is negligible. However, greater acidity and stronger acid sites present on alkali-earth supports provide a high catalytic activity. The deactivation rate and the amount of coke determined by TG are related. The nature of the coke was discussed on the basis of DSC results obtained during the coke burning. Coke deposited on alkali and alkali-earth Mβ zeolite during then-heptane transformation becomes progressively more stable as the support acidity and the time on stream increase. The localization of Pt particles and their proximity to the acid sites influence the coke composition and its removal. The regeneration of Pt/Kβ was performed and the results showed that the catalyst fully recovers its catalytic behaviour.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
