01211nab a2200169 4500 20260520000814.0 260224s2009 xxu Studying the effect of barium modification on the acidic properties of ultrastable HY zeolite ene. 2009 14/04/2009 ; 14/04/2009 4 p. ; 46-50 Transcripción del resúmen publicado por el autor: The effect of barium modification of ultrastable HY zeolite on its acidic properties was investigated using different techniques. Temperature-programmed desorption (TPD) of ammonia results showed the presence of only weak acid sites at 287 °C in HY zeolite. Because of barium modification, the number of acidic sites decreased but the strength of these sites was higher than purer HY zeolite. Magic angle spin nuclear magnetic resonance (MAS NMR) spectra indicated the reduction of acidity after barium impregnation. Reduction of the number of acid sites because of barium modification was also confirmed by the n-hexane cracking reaction test. Energy & fuels 23 ARTICULO Shakir Seddigi, Zaki 40818 169536 169536 0 0 0 0 237355 BAAB BAAB 2026-03-05 200044338 0 200044338 2026-03-05 15:11:45 2026-03-05 ARTICULO