The skeletal isomerization of n-butenes over a chlorinated alumina catalyst has been studied, by operating under reaction-regeneration cycles in an isothermal fixed-bed integral reactor. The limiting values of the reaction and regeneration temperatures for avoiding irreversible deactivation by loss of chlorine have been determined. Reversible deactivation by deposition of coke, which is completely removable by combustion, is unavoidable. The effect of the operating conditions upon the deposition of coke and the deterioration of the porous structure as a consequence of the deposition have been analyzed.