Isobutene oligomerization was performed using a ceramic membrane with a film of zeolite beta, where three different zeolite molar ratios SiO(2)/Al(2)O(3) were evaluated. The reaction was studied in a membrane reactor within the 373-423K temperature range. Analyses of the reaction products suggest a complex pattern of isobutene dimerization and isomerization and the main reaction product was 2,2,4 trimethypentane (2,2,4 TMP) for all catalytic tests conducted. (C) 2010 Elsevier B.V. All rights reserved.