C2-C4 light olefins from bioethanol catalyzed by Ce-modified nanocrystalline HZSM-5 zeolite catalysts

Conversion of bioethanol into bulk chemicals besides ethylene is a promising process in which the stability of catalyst and the selectivity of products are important. In this study, a series of Ce-modified nanocrystalline HZSM-5 catalysts were prepared and their catalytic performance in the conversion of bioethanol into C-2-C-4 light olefins was investigated in a fixed-bed reactor at 400 degrees C under atmospheric pressure. The results show that the stability of catalyst and the distribution of products depend strongly on the content of cerium and the calcination temperature: both cerium content and calcination temperature affect not only the acid properties of the tested catalyst samples but also the composition of cerium species (Ce3+/Ce4+) as revealed by XPS. Among the tested catalyst samples, the catalyst with 5 wt% cerium loading and 520 degrees C calcination temperature exhibits the best stability and selectivity to C-3-C-4 light olefins. (C) 2011 Elsevier B.V. All rights reserved.