Poisoning and regeneration of claus alumina catalysts

Samples of poisoned alumina catalysts obtained from Claus sulfur recovery plants in Alberta have been regenerated. Poisoned catalysts had SO4=, NO3−, sulfur and carbon deposits, discoloration, and low surface areas. Whereas the Claus catalytic activity of the poisoned catalysts varied widely, regeneration uniformly enhanced the catalytic activity to the same level as fresh alumina. The activity comparisons were made under conditions similar to those of a third Claus converter of low partial pressures of H2S and SO2 and high partial pressure of H2O, where maximum catalytic activity is required to promote Claus reaction.