ISOMERIZATION OF N-BUTANE OVER NI SO42--ZRO2

n-Butane isomerization was studied on nickel supported on SO42- - ZrO2 and compared with SO42- - ZrO2 and Pt/SO42- - ZrO2. Reaction conditio ns were 300 degrees C, WHSV = 1 h(-1), atmospheric pressure and severa l H-2/n-C-4 ratios. Metallic phases (Ni or Pt) do not show typical pro perties of supported metallic functions. The metal limits its role to the 'activation' of hydrogen. The activated hydrogen inhibits the form ation of a carbonaceous deposit which affects the strong acid sites an d is the cause of SO42- - ZrO2 deactivation. Nickel has less capacity than platinum to activate hydrogen and requires greater metal loads an d higher partial pressures of hydrogen in order to give stability to S O42- - ZrO2 for n-butane isomerization.