Influence of the phosphorus addition ways on properties of CoMo-catalysts of hydrotreating

Surface‐Dependent Activation of Model α‐Al2O3‐Supported P‐Doped Hydrotreating Catalysts Prepared by Spin Coating

“…For instance, co‐impregnation of phosphorus and metal precursors modifies the chemical structure of the deposited precursor by forming heteropolyanions, [19, 38, 40] which may have an effect both on Mo dispersion and posterior catalyst activation. On the other hand, prior P‐doping of the support influences the acidity of the support [36, 37, 44] . The effect exerted by phosphorus is most probably surface‐dependent, since the interaction of phosphorus with alumina is controlled by the speciation of the alumina sorption sites which are different on each crystal plane (see Figure 1).…”

“…This work aims at increasing the complexity of the model systemss tudied previously [24,25] by adding phosphorus in the catalystc omposition. This dopant is widely used in industrial formulations since there is general agreement that it leads to an increase in HDS activity [36][37][38][39][40][41][42] by reducing the interactions betweent he active phase and the support as phosphates block the basic surface Al-OH sites that selectively interact with the Mo active phase. It has also been reportedt hat phosphorusc an improveM od ispersion.…”

“…On the other hand, prior P-doping of the support influences the acidityo ft he support. [36,37,44] The effect exertedb yp hosphorus is most probably surface-dependent, since the interaction of phosphorus with aluminai sc ontrolled by the speciation of the alumina sorptions ites which are different on each crystal plane (see Figure 1). However,s uch surface-dependent P-doping has never been investigated in the literaturebefore.…”

Recycling the CoMo/Al2O3 catalyst for effectively hydro-upgrading shale oil with high sulfur content and viscosity

“…Two typical such kinds of compounds are 4-methyl dibenzothiophenes (4-MDBTs) and 4,6dimethyl-dibenzothiophenes (4,6-MDBTs), which are difficult to be converted to sulfur-free compounds because of the steric hindrance imposed by the substituting alkyl groups at 4,6 positions. 11,12 Intensive efforts have been made to modify CoMo/Al 2 O 3 to increase its deep hydrodesulfurization activity, including optimizing the balance in Co/Mo ratio as investigated by Al-Zeghayer et al, 8 ne-tuning the properties of the alumina support as reported by Zhang et al, 13 and the addition of promoters like F, B and P. 14,15 Alumina has always been the rst choice as the support material for HDS catalysts, due to its stability, acidity, and high surface area. The composites of alumina and silica or zeolite have also been tested as support material for hydrodesulfurization catalysts.…”

Effect of Phosphorus Modification on the Acidity, Nanostructure of the Active Phase, and Catalytic Performance of Residue Hydrodenitrogenation Catalysts

“…The results show that the acid amount of the catalyst prepared by modified co-impregnation increased significantly, while the increase of the acid amount of the catalyst prepared by step impregnation was not obvious, and the former catalyst showed higher activity. Vatutina et al 18 adopted different modification methods to modify the CoMo hydrotreating catalyst using H 3 PO 4 , and found that the direct impregnation method improved the HDS performance more obviously. At the same time, it was found that the addition of phosphorus increased the stacking number of the active phase of the catalyst.…”