The reduction characteristics of nickel catalysts have been investigated by thermoconductivity-temperature-programmed-reduction (TC-TPR) technique. Results showed that on these catalysts there exist three species of nickel oxide
for which the reduction temperatures were 400-500
600-650
>750℃ and activation energies were 16.1
28
5
65.5 kcal/mole
respectively. Their relative contents were markedly affected by preparation method
pretreatment conditions and reoxidation temperatures of the catalysts. Therefore
these species of nickel oxide are mutually convertible according to operating conditions.