Semi-continuous regeneration of sulfur-contaminated catalytic conversion systems

摘要

The process of oxidatively regenerating in situ a fixed bed hydrocarbon catalyst which is sensitive to reactive sulfur compounds in a conversion system having sulfur-contaminated vessels and/or conduits in the flow path upstream from said catalyst is improved by passing regenerating oxygen-containing gas first through the sulfur-contaminated vessels and/or conduits and then through the fixed catalyst bed while limiting the water content of the regenerating gas to a concentration of not more than 0.1 mol percent throughout the flow path and at a temperature in the range of 750 DEG -1100 DEG F. to oxidize the sulfur contaminants in the vessels and/or conduits upstream from the catalyst. Thereby the evolved sulfur oxides flow through the fixed bed catalyst in the absence of sufficient water which would promote reaction of sulfur oxides with the catalyst. The low water content regenerating gas is continued until substantially all the oxidizable sulfur contaminants are removed from the vessels and/or conduits. Thereafter, carbonaceous deposits are oxidized from the catalyst.