Chelating Agents Modified Hydrotreatment Catalysts for Selective Hds and Aromatic Hydrogenation

摘要

Hydrotreatment catalysts (Co-Mo, Ni-Mo and Ni-W/Al_2O_3) were prepared by an impregnation method using a chelating agent (nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA) or cyclohexanediaminetetraacetic acid (CyDTA)) containing solution, and were supplied for some test reactions (hydrodesulfurization of benzothiophene and dibenzothiophene, and hydrogenation of o-xylene and l-methylnaph thalene). The chelating agents modified Co-Mo and Ni-W/Al_2O_3 showed higher activities both in hydrodesulfurization (HDS) and hydrogenation (HGN) than those of the catalysts without the modification. The chelating agents showed little effect on the activities of Ni-Mo/Al_2O_3. CyDTA was mostly effective both for HDS activity of Co-Mo/Al_2O_3 and HGN activity of Ni-W/Al_2O_3. The chelating agents showed no effect on the activity of each component catalysts (i.e. Co, Ni, Mo, and W/Al_2O_3). The interaction between Co (or Ni) ion and the chelating agents are important for this improving effect.