Sulfur poisoning of cobalt and iron fischer-tropsch catalysts

摘要: Abstract A cobalt/silica and four iron catalysts (unsupported, silica-supported, K-promoted borided) were exposed to 0.5–8 ppm H 2 S either in situ a 2/1 /CO reaction mixture or pure hydrogen. Catalyst activity selectivity monitored as function of sulfur coverage. Monolayer surface sulfides are formed on the at concentrations below 500 K, while bulk higher lower temperatures. Loss is greater during poisoning compared presulfiding for equivalent S/metal coverages. Iron boride significantly more resistant than unpromoted iron. At sufficiently low CO hydrogenation increases with time. The average molecular weight hydrocarbons produced by cobalt through maximum increasing exposure S. product distribution essentially unaffected su fur poisoning.