Deshidratación en fase líquida de 1-feniletanol utilizando sólidos ácidos microporosos

NICOLÁS M. BERTERO; HORACIO CABRAL; CARLOS R. APESTEGUÍA; ALBERTO J. MARCHI

Buenos Aires

Congreso; XXII Congreso Interamericano y V Congreso Argentino de Ingeniería Química; 2006

The liquid-phase dehydration of 1-phenylethanol (FE) was studied at 363 K on different zeolites. The catalyst activity and selectivity greatly depended on the nature, density and strength of surface acid sites and the microporous structure as well. Zeolites which contain similar density of Brönsted (B) and Lewis (L) acid sites (HY, HBEA, HZSM-5), dehydrated FE directly to styrene (ES) and also via the formation of alfa-methylbenzyl ether (ET); both products were consecutively transformed to heavier products (PP). The shape selectivity increased ES yield in case of HZSM-5, and no PP were formed. On the other hand HY deactivated very fast because of these PP which block the porous structure. An intermediate behaviour was shown by HBEA which form these PP but they are able to diffuse out of the structure. On mordenites samples, the Si/Al ratio was important for increasing the selectivity to ES and diminishing to ET, and this ratio also affected the activity, showing a maximum. On these zeolites ES formation required stronger acid sites than ET formation. NaY sample, containing exclusively L acid sites of weak strength exhibited no activity.