EFFECT OF COKE AND CATALYST STRUCTURE ON OXIDATIVE REGENERATION OF HYDROPROCESSING CATALYSTS

Two industrial hydroprocessing catalysts used for upgrading an atmospheric residue and a gas oil, respectively were regenerated in a fixed bed using air and 2 vol.% O2 + N2 balance mixture. The regeneration in air resulted in a significant sintering of the catalyst's material. The surface area of catalysts regenerated in 2 vol.% O2 mixture was similar to that of fresh catalysts, whereas a significant loss of surface area was observed after regeneration in air. The X-ray diffraction pattern of catalysts regenerated in 2 vol.% O2 + N2 balance mixture were also similar to that of fresh catalysts.