Transformation of light alkenes over templated and non-templated ZSM-5 zeolites

The transformations of ethene, propene and i-butene over templated (CVN) an d non-templated (CVM) ZSM-5 zeolites at 350 degrees C were examined. The in itial activity values obtained for the conversion of C2H4 were significantl y higher with H-CVM than with H-CVN zeolite, in accordance with the stronge r acidity of its sites. Tn contrast, for the transformation of C3H6 and i-C 4H8 the opposite order was observed: the more acidic catalyst presents a lo wer activity. It was also observed that, in the case of CVM, the sodium-exc hanged CVM samples have higher activities than the H form. These observatio ns can be related to the extremely high acidity of the CVM samples. (C) 199 9 Elsevier Science B.V. All rights reserved.