Regeneration and reactivation of reforming catalysts while passivating

Abstract

A process for the regeneration and reactivation of coked iridium-containing catalysts, and chemical modification and passivation of iron scale carried over from a ferrous metal regeneration circuit to the catalyst-containing reactor, or reactors, to suppress reaction between the iron scale and catalyst as normally occurs when iron scale contacts the catalyst of a reactor, or reactors. The iron scale is rendered non-reactive or inert in the reactor environment by converting the iron scale to a passive form, preferably ferric oxide, by employing ab initio an extended low temperature primary burn while purging the system of carbon oxides, notably carbon monoxide and carbon dioxide. Thereafter, the agglomerated metal, or metals, component of the catalyst is redispersed at conditions insufficient to reduce the oxidized iron scale which is contained in admixture with the regenerated catalyst. The agglomerated metal, or metals, component of the regenerated catalyst contained in admixture with the passivated iron scale is redispersed in a non-reducing atmosphere to return the catalyst to its active state without reduction of the passivated iron scale. This process is an improvement in those described in U.S. Pat. No. 4,514,284 and U.S. Pat. No. 4,517,076, respectively.