Acidity modifications of nanozeolite-Y for enhanced selectivity to olefins from the steam catalytic cracking of dodecane.

ABSTRACT: Nanozeolite-Y was synthesized in the absence of a templating agent with several modification methods. The parent nanozeolite-Y was prepared with different sodium (Na) contents and crystallization conditions. Then, the parent nanozeolite-Y was modified by ion exchange, calcination, and steam treatment. The treatment caused insignificant changes to the ratio of alumina and silica but altered the zeolite acid sites. The Lewis and Brønsted acidity changed after the treatment depending on the modification approach, as indicated by the FTIR spectroscopy of pyridine. The ammonia temperature programmed desorption (NH₃-TPD) confirmed that the acid sites consisted of weak and medium sites, which decreased after modifications. Moreover, the solid-state nuclear magnetic resonance (NMR) spec

SUBMITTER: Shafei EN 

PROVIDER: S-EPMC9210351 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature