Piperidine hydrogenolysis on a commercial hydrocracking catalyst III. The effects of zeolite unit cell size, catalyst sulfur content, and coke deposition on catalyst activity and deactivation

摘要: A group of fresh, deactivated, and deactivated-regenerated commercial hydrocracking catalysts was characterized using piperidine hydrogenolysis as a probe reaction at 301C, hydrogen partial pressures about l6 atm, initial concentrations ranging from 4.14 × 10−3 11.86 g mol/liter. The first part the study examined effects zeolite unit cell size on activity catalyst deactivation revealed that over range (24.35-24.56 A), adsorption equilibrium constants associated with acidic metallic functions decreased while rate increased increasing size. increase function is explained in terms total number potential acid sites present per cell. suggested to reflect mostly changes upon regeneration. Different types are proposed exist order account for results. An inverse relationship between generally observed both functions. These results point possible parameter correlating catalytic well selectivity, especially function. second wt% sulfur carbon low levels coke showed regenerated constant (≈24.40 ( 2.5 wt%) deactivated had similar activities. Between 2 6 carbon, linearly content catalyst. At (< 1.5 wt%), effect prevailed. found have no rates during reactions.