Regeneration of amorphous NiB/SiO2 catalysts deactivated in cyclopentadiene hydrogenation

An amorphous NiB/SiO2 catalyst, deactivated in the partial hydrogenation of cyclopentadiene to cyclopentene, was regenerated by an oxidation-reduction method. After regeneration, the activity was recovered and the selectivity almost recovered. The data of BET, H-2 uptake and XPS measurements on the regenerated catalyst are almost the same as the original counterpart. XRD a nd DSC tests revealed that some crystallization had occurred over the regen erated catalyst, which led to the selectivity decreasing slightly. This reg eneration was repeated several times, but the structural and chemical prope rties were nearly the same as after the first operation. (C) 2000 Society o f Chemical Industry.