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A fractional factorial design 2 5−1 was used to evaluate the effect of temperature, time, and the ratios TEAOH/SiO 2 , Si/Al, and H 2 O/SiO 2 in crystallization of Al-rich zeolite Beta. The main effect of TEAOH/SiO 2 ratio was not significant. However, the Al-rich BEA structure was formed when partially substituting the tetraethylammonium cations by Na + . The activity and selectivity to bi-branched isomers in isomerization of n -hexane is directly proportional to the amount to Al atoms in the crystal lattice of BEA structure. TPD-NH 3 analyses showed that the improvement of such properties may be a result of the increased amount of Brønsted acid sites on the zeolite surface. XANES analyses with bimetallic Pt/Ni catalysts demonstrated that, at reduction temperatures higher than 673 K, the reduction degree of Ni does not influence the activity of isomerization of n -hexane. Instead, the metal particles become more agglomerated and the activity decreases considerably. It is supposed that the rate limiting step of isomerization is the protonation of n -hexane on the Brønsted acid sites of zeolites. [ABSTRACT FROM AUTHOR]