Influence of the treatment of mordenite by ammonium hexafluorosilicate on physicochemical and catalytic properties
1996; Elsevier BV; Volume: 16; Issue: 4 Linguagem: Inglês
10.1016/0144-2449(95)00138-7
ISSN1873-3115
AutoresJoão M. Silva, M.F. Ribeiro, Fernando Ramôa Ribeiro, E. Benazzi, N.S. Gnep, M. Guisnet,
Tópico(s)Minerals Flotation and Separation Techniques
ResumoDifferent samples were prepared by treating a NH4MOR sample (Si/Al = 5) with ammonium hexafluorosilicate. The dealumination of the outer surface of mordenite crystallites was more pronounced than that of the bulk. A decrease in the adsorption rate and capacity for organic molecules and in activity and stability for m-xylene transformation was observed. Furthermore, the isomerization selectivity was improved because of inhibition of desorption of bulky products of m-xylene disproportionation. All of these observations can be related to a dealumination of the mordenite limited to the pore mouth with deposit, at the entrance of channels, of aluminum species extracted from the framework.
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