Hydrodesulfurization, Hydrodenitrogenation and Hydrodearomatization over CoMo/SAPO-11-Al₂O₃ Catalysts

Abstract

Several SAPO-11-Al2O3 supports with different amounts of SAPO-11 were used to prepare a series of CoMo/ SAPO-11-Al2O3 catalysts by the impregnation method with or without addition of citric acid. Hydrodesulfurization (HDS) of 4,6-dimethyldibenzothiophene, hydrodenitrogenation (HDN) of acridine, and hydrodearomatization (HDA) of o-xylene, 1-methylnaphthalene and phenanthrene were carried out to evaluate the catalytic activity of the catalysts. The catalysts were characterized by BET, XRF, NH3-TPD, XPS and TEM. The acidity of the supports strongly affected the active slabs structure and activity of the catalysts. 20 wt% SAPO-11 added catalyst showed lower HDA, HDS and HDN activities compared to CoMo/Al2O3 catalyst. The length and stacking number of CoMoS active slabs on the former increased because of decreased dispersion of Mo species due to the reduction in number of strong acid sites on the support surface in the presence of SAPO-11. Addition of citric acid during active metal impregnation decreased HDA activity but increased HDS and HDN activities due to improvement of Mo species dispersion, resulting in formation of shorter length and higher stacking of CoMoS active slabs.

Ar2+ Beam Irradiation-Induced Multivancancies in MoSe2 Nanosheet for Enhanced Electrochemical Hydrogen Evolution

“…Panels g and h of Figure provide high-resolution XPS spectra of Mo 3d and Se 3d, respectively. In Figure g, Mo 3d 3/2 and 5/2 peaks are located at 231.8 and 228.7 eV, respectively, suggesting the existence of Mo 4+ in MoSe 2 . Nevertheless, unlike pristine MoSe 2 , Mo 6+ peaks gradually arose in Ar 2+ -5e14 and Ar 2+ -5e15, indicating the high oxidation state caused by the increasing dangling bonds of Mo atoms .…”

“…In Figure 1g, Mo 3d 3/2 and 5/2 peaks are located at 231.8 and 228.7 eV, respectively, suggesting the existence of Mo 4+ in MoSe 2 . 36 Nevertheless, unlike pristine MoSe 2 , Mo 6+ peaks gradually arose in Ar 2+ -5e14 and Ar 2+ -5e15, indicating the high oxidation state caused by the increasing dangling bonds of Mo atoms. 37 A similar phenomenon was also observed in Se, where the peaks sites of Se 3d 3/2 and 1/2 shifted to the higher binding energy (from 53.…”

Effect of TiO2 Coating on Morphology of Active Phase on Sulfided CoMo/Al2O3 Hydrotreating Catalysts

“…In our previous study, to clarify the correlation between the morphology of active slabs and catalytic activity, we focused on the interaction of active metal and support of the catalyst. Since the acidity of the support is expected to affect the hydrogenation activity, , by addition of SAPO-11, a zeolite with a large amount of weak acid sites, to an Al 2 O 3 support of the CoMo catalyst, we found that the formation of HDS, HDN, and HDA active phases was dramatically affected by improvement of the surface of the support . Incidentally, both HDS and HDA activities decreased with the addition of SAPO-11.…”

“…The loading amount of MoO 3 and CoO were determined by XRF measurement using Rayny EDX-700/800XRF analyzer (Shimadzu Co.). A 200 mg portion of catalyst samples was crushed and then compression molded into a shaped disk before obtaining an analyzing system …”

Roles of Promoter and Support of Sulfided Mo-based Catalyst in Selective Hydrotreating of Palm Fatty Acid Distillate

“…The loading amounts of CoO, MoO3, and TiO2 were determined by X-ray fluorescence (XRF) measurement using a Rayny EDX13 700/800XRF analyzer (Shimadzu Corp.). Catalyst samples 200 mg were crushed, then compression molded into a shape disk before analyzing 23) .…”