Characterization of coke on spent resid catalyst from ebullating bed resid and its effect on activity

This paper describes the nature of carbon and feed metals deposition on aged resid catalyst. A series of aged resid hydrotreating catalysts from a three stage expanded bed pilot plant has been studied using nuclear microphobe temperature programmed oxidation, solid state NMR spectroscopy and elemental analyses. These techniques have been used to characterize the relationship between activity functions and the carbonaceous and metal deposits.