REACTIONS OF N-HEPTANE AND METHYLCYCLOPENTANE OVER AN OXYGEN-MODIFIEDMOLYBDENUM CARBIDE CATALYST - STUDY OF COKE FORMATION, CATALYST DEACTIVATION, AND REGENERATION

After an oxidative treatment, molybdenum carbide is an active and very selective catalyst for the isomerization of n-heptane. An important p arameter in the choice of a catalyst for application in industry is it s resistance to deactivation by coke formation, which can be caused by the presence of cyclic molecules. In this work, a study of the effect of methylcyclopentane (MCP) on the deactivation of the oxygen-modifie d molybdenum carbide catalyst has been performed. It has been found th at the catalyst deactivates in the presence of pure MCP and that a low er activity for heptane isomerization is obtained after the reaction u nder MCP. TEM showed that coke formation is the cause of the deactivat ion. It has also been shown that increasing the total pressure when th e MCP is reacted leads to a large decrease in the catalyst deactivatio n and that heptane isomerization can be carried out over this deactiva ted sample with only a small loss in activity. Further, the catalyst c an be totally regenerated in air.