Selective Ring Opening of Ethylbenzene on Bifunctional Catalyst Pt–Ir over Hierarchical USY Zeolite

• Published in: Petroleum chemistry 2020, Vol.60 (1), p.104-112
• Main Authors: Elena Pérez-Guevara, Molinillo, Jose M. G., Martínez de la Ossa, Enrique J., Frontela, Juana, Lázaro, Jesús, Franco, María José
• Format: Article
• Language: English
• Subjects: Bimetals; Catalysts; Cetane number; Chemistry; Chemistry and Materials Science; Continuous flow; Ethylbenzene; Hydrogenation; Industrial Chemistry/Chemical Engineering; Ion exchange; Iridium; Nuclear fuels; Paraffins; Ring opening; Zeolites
• ISSN: 0965-5441; 1555-6239
• DOI: 10.1134/S0965544120010119

A bifunctional catalyst for selective ring opening (SRO) has been designed using a hierarchical zeolite as support. This material was prepared introducing additional mesoporosity in the microporous structure of a USY zeolite, by surfactant-templating post-synthetic mesostructuring process. Monometallic and bimetallic Pt( x )−Ir( y ) catalysts with different metal loadings and Pt/Ir mole ratio have been prepared. In addition, to optimise the acid-metal balance, the acidity of the support has been modulated via ion-exchange process with Na + . The catalytic behaviour of the prepared materials has been evaluated with ethylbenzene hydrogenation and SRO simultaneous reaction in a continuous-flow fixed-bed reactor, at 275°C and 3 MPa. Pt(2)−Ir(1) resulted the most promising metallic combination. The high hydrogenolytic activity of Ir, along with the high hydrogenation activity and cracking limitation of Pt attained a high paraffins production. This behaviour was improved modulating the acidity of the support. Thus, Pt(2)−Ir(1)/Na−FAU−CTAB catalyst maximized the yield to paraffins which improve the cetane number of fuels.