The reaction between isobutane and olefins to produce high octane gasoline components is undustrially catalyzed by liquid acids such as H_2SO_4 of HF. Recently, however, environmental concerns about these liquid acids have prompted the indistry to consider alternative solid acids such as zeolites (1). While zeolites can effectively catalyze the reaction between isobutane and butenes to produce isooctanes iwth high selectivity, these catalysts deactivate too rapidly, to allow for an immediate implementaton of technology based on solid acids. There has been significant speculation and indirect conclusions on the nature of the deactivation process during soild catalyzed alkylation. Several authors (2,3), working in fixed bed conditions and with low olefin conversions have suggested that olefin oligomerization is primarily responsible for catalyst deactivation. More recent work (1) performed under well strired conditions has indicated that it is possible to achieve complete olefin conversion for a substantial length of time with zeolite catalysts suc as H-BEA. Further improvements in the lifetme of zeolite based catalysts will, therefore, need to address the actual causes of actalystdeactivation and develop strategies to mitigate this problem through effective catalyst regeneration. In this work,. we describe and discuss the principal causes and consequences of the deactivation of zeolite H-BEA during the alkylation of isobutane with cis-2-butene,
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