초록 ▼

A process wherein a coked, deactivated iridium-containing catalyst can be reactivated in a sequence of burn steps, inclusive of a low temperature primary burn step and a subsequent high temperature burn step. In (1) the low temperature primary burn step (i) the chloride level of the catalyst is rais

A process wherein a coked, deactivated iridium-containing catalyst can be reactivated in a sequence of burn steps, inclusive of a low temperature primary burn step and a subsequent high temperature burn step. In (1) the low temperature primary burn step (i) the chloride level of the catalyst is raised and the catalyst passivated by contact with a hydrogen chloride containing gas, (ii) and coke is then burned from the catalyst by contact with a gas which contains hydrogen chloride at level sufficient to suppress iridium agglomeration at a level of oxygen providing burn temperatures which do not exceed about 425°C., this being sufficient to remove a preponderance of the coke without agglomeration of the iridium component. (2) In a high temperature secondary burn step the catalyst is subjected to (iii) a chlorination step wherein the catalyst is contacted with a hydrogen chloride containing gas sufficient to redisperse any agglomerated iridium, if any, produced during the low temperature primary burn, and raise the chloride level of the catalyst to a yet higher level for suppression of iridium agglomeration at higher temperature than 425°C., (iv) residual coke is then burned from said catalyst by contact with a gas which contains hydrogen chloride at level sufficient to suppress iridium agglomeration at a level of oxygen sufficient to provide temperatures greater than 425°C., sufficient to burn residual coke from the catalyst. The high chloride catalyst can then be (3) stripped with steam, or steam and hydrogen chloride to reduce the level of chloride.

대표청구항 ▼

In a process for the catalytic conversion of hydrocarbons wherein a hydrocarbon feedstock is contacted with a catalyst comprised of an iridium component composited with a porous refractory inorganic oxide support at hydrocarbon conversion conditions, the catalyst having been at least partially deact

In a process for the catalytic conversion of hydrocarbons wherein a hydrocarbon feedstock is contacted with a catalyst comprised of an iridium component composited with a porous refractory inorganic oxide support at hydrocarbon conversion conditions, the catalyst having been at least partially deactivated during contact with said feedstock by coke deposition thereon, said catalyst having been regenerated after discontinuing contact of said catalyst with said feedstock in a series of steps which include (i) providing a bed of said catalyst in a reaction zone with a chloride level on the catalyst ranging from about 0.9 percent to about 1.5 percent, based on the weight of the catalyst, (ii) burning a preponderance of the coke from the catalyst while adding a gas containing hydrogen chloride sufficient to maintain the chloride level on the catalyst within a range of from about 0.9 percent to about 1.5 percent, based on the weight of the catalyst, and oxygen in concentration ranging up to about 5000 parts, based on the volume of gas, to provide a flame front temperature not exceeding about 425°C. sufficient to burn the coke from the catalyst, but wherein the iridium component of the catalyst is agglomerated as via inadvertent departure from the prescribed burn conditions, (iii) the chloride level of the catalyst is increased further to at least about 1.6 percent, based on the weight of the catalyst, the improvement comprising contacting said catalyst subsequent to raising the chloride level of the catalyst as in (iii) with a gas containing hydrogen chloride in concentration ranging from about 150 parts to about 5000 parts, based on the volume of the gas, and up to about 5000 parts per million parts oxygen, based on the volume of the gas to provide a flame front temperature greater than about 425°C. sufficient to redisperse the agglomerated iridium and substantially complete the removal of coke from the catalyst.