Impact of the Desilication Treatment of Y Zeolite on the Catalytic Cracking of Bulky Hydrocarbon Molecules

JUAN RAFAEL GARCÍA; MARISA FALCO; ULISES SEDRAN

TOPICS IN CATALYSIS

SPRINGER/PLENUM PUBLISHERS

Lugar: New York; Año: 2016 vol. 59 p. 268 - 277

1022-5528

Mesoporosity was induced on a USY zeolite bymeans of an alkaline leaching process. Samples wereimmersed in 0.05, 0.10 and 0.20 M NaOH solutions during15 min at room temperature and then were exchanged withNH4? ions and calcined to yield the acid forms. The formationof mesopores with size ranging from 20 to 100 A °increased with the concentration of NaOH. The modifiedzeolites were used at 30 wt% to formulate cracking catalystswith an inert SiO2 matrix. The catalytic performanceof these catalysts in the conversion of 1,3,5-tri-isopropylbenzenewas evaluated in a batch, fluidized bed reactor at450, 500 and 530 C, with a catalyst to oil relationship of4.7 and contact times up to 16 s. The catalysts with themodified zeolites were more active in the cracking of thesebulky molecules than the one with the parent, unmodifiedzeolite; moreover, the selectivity to the products of primarycracking reactions increased. These results reveal anenhanced diffusion of the reactant molecules to the zeoliteactive sites and of the products out of the catalyst particles.