Temperature dependence of the USHY+HZSM-5 mixing effect on the n-heptane transformation

The temperature dependence of the USHY + HZSM-5 zeolites mixing effect on t he catalytic properties for the n-heptane transformation is analysed; sever al mixture compositions were tested at 350, 400 and 450 degreesC. The obser ved activities and product selectivities for the mixtures were compared to the predicted ones based on the pure zeolite tests assuming its relative co ntributions to the product yields and conversion with no mechanistic intera ctions. The most important detected synergism in the product selectivities, which is the increased C-4 products ramification, is reduced with the temp erature rising. (C) 2001 Elsevier Science B.V. All rights reserved.