Ring opening of methylcyclohexane over platinum-loaded zeolites.
The activity of different platinum-loaded zeolites (Mordenite, ZSM-12, ZSM-5, ZSM-23) was investigated in the hydroconversion of methylcyclohexane (MCH), in the context of upgrading highly aromatic distillates for fuel blending. In all cases, conversion of MCH proceeds according to a pathway where the primary products are a mixture of dimethylcyclopentanes and ethylcyclopentane formed by isomerization and ring contraction of MCH. The primary products undergo consecutive ring-opening reactions with formation of n- and isoheptanes. The latter further react to form lower-molecular-weight n- and isoalkanes. The selectivity and distribution of products deriving from ring-contraction and ring-opening reactions are strongly affected by the pore size and topology of the zeolites. ZSM-5 exhibits a strong reactant shape-selectivity effect on ring-opening products. The evaluated zeolites show the following order of activity in the conversion of methylcyclohexane: Mordenite>ZSM-12>ZSM-5>ZSM-23.
Calemma
Vincenzo
V
Eni R&M Division, Via Maritano 26, San Donato Milanese, Milan, Italy. vincenzo.calemma@emi.it
Carati
Angela
A
Flego
Cristina
C
Giardino
Roberto
R
Gagliardi
Federica
F
Millini
Roberto
R
Bellussi
Giuseppe
G
D002384:Catalysis; D003510:Cyclohexanes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D010984:Platinum / Q000737:chemistry*; D016062:Porosity; D017641:Zeolites / Q000737:chemistry*
D003510:Cyclohexanes; D017641:Zeolites; D010984:Platinum; C521475:methylcyclohexane