2013-05-292013-05-292011-10GARCIA, Fillipe A. C., et al. Effect of cerium loading on structure and morphology of modified Ce-USY zeolites. Journal of the Brazilian Chemical Society, São Paulo, v. 22, n. 10, p. 1894-1902, out. 2011. Disponível em: <http://www.scielo.br/pdf/jbchs/v22n10/v22n10a10.pdf>. Acesso em: 22 maio 2013. <http://dx.doi.org/10.1590/S0103-50532011001000010>.0103-5053https://repositorio.ufpa.br/handle/2011/3929This work describes comprehensibly the effect of cerium loading on the structure and morphology of NH4USY zeolite. The Ce-USY (2-25 wt.% of CeO2) was obtained by wet impregnation of CeCl3 followed by calcination at 550ºC for 8 h. At low loadings (2-10%), cerium species are mainly located at ion exchange positions in the framework, whereas at higher loadings (15-25%), small aggregates were formed on the HUSY surface. X-ray diffractograms (XRD) exhibited only the reflections related to HUSY, demonstrating the high dispersion of cerium species, but Fourier transform Raman spectroscopy (FT-Raman) detected CeOx for the materials above 10%. Reaction of CeCl3 with NH4USY produced NH4Cl, which decomposed to form HCl, leading to framework dealumination. The materials showed an increased Lewis/Brønsted ratio with increasing cerium loadings due to the interaction between the excess cerium and the OH groups of USY, and the consequent formation of CeOx species.engAcesso AbertoZeólita de cério USYÓxido de cérioTroca de íons em estado sólidoEspectroscopia de Al e Si MAS NMRArtigo de Periódico