Methanation over transition metal catalysts III. Co/Al2O3 in sulfur-poisoning studies

摘要: Abstract Poisoning of Co Al 2 O 3 by H2S in CO hydrogenation was studied an all-quartz recycle reactor; the studies were carried out at atmospheric pressure and 390 °C with feed gas containing 1 to 4% H2 13 100 ppb H2S. Sulfur-poisoned catalysts analyzed using Auger electron spectroscopy (AES). Addition reduced steady-state methanation activity more than 103-fold °C; 90 104-fold. AES showed that loss resulted from two-dimensional surface sulfide formation; no sulfur present subsurface regions. In poisoning , carbon plays only a secondary role. appears be due primarily geometric blockage sites, one atom adsorbed per two atoms. Electronic effects adsorption are also important as evidenced 12 kcal/mole reduction activation energy for upon poisoning.