Leaching of heavy metals under ambient resembling conditions from hydrotreating spent catalysts

摘要: Abstract Spent hydrotreating catalysts are not inert to air, humidity and temperature, as the combination of these factors may gradually leach metals from catalyst causing contamination land groundwater. In order investigate combined effect ambient variables on leaching, a spent is placed in tin can heated at 40–50 °C then treated for 1000 h under continuous flow wet air. Said contains 10.68 wt.% V, 0.43 wt.% Fe, 2.67 wt.% Ni 3.78 wt.% Mo well 14.7 wt.% coke 19.4 wt.% sulfur, latter basically form metallic sulfides. During leaching experiment, samples taken different times track evolution coke/sulfur content. At end test, even though relatively low temperatures used, fully removed, V partially extracted (around 25% each metal) while Fe content increases. Practically no observed sulfur/coke-free fresh subjected an identical experimental procedure. The presence sulfur clearly enhances leaching. oxides produced oxidation sulfides with water, results formation acidic species, which have strong positive influence catalyst.