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Коган, В. М.; Parfenova, N. M.; Gaziev, R. G.; Rozhdestvenskaya, N. N.; Korshevets, I. K.

doi:10.1023/a:1025110621502

Cited by 14 publications

(6 citation statements)

References 31 publications

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“…Moreover, we assume that the DDS and the HYD sites are the same and that the only factor, which determines the HDS pathway, is the adsorption conformation of the S-containing molecule. Kogan et al also suggested that the HYD pathway of the HDS of thiophene takes place at the same catalytic sites as the DDS pathway [44].…”

Section: Discussionmentioning

confidence: 99%

Competitive hydrodesulfurization of 4,6-dimethyldibenzothiophene, hydrodenitrogenation of 2-methylpyridine, and hydrogenation of naphthalene over sulfided NiMo/γ-Al2O3

Egorova

Prins

2004

Journal of Catalysis

144

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Section: Discussionmentioning

confidence: 99%

Competitive hydrodesulfurization of 4,6-dimethyldibenzothiophene, hydrodenitrogenation of 2-methylpyridine, and hydrogenation of naphthalene over sulfided NiMo/γ-Al2O3

Egorova

Prins

2004

Journal of Catalysis

144

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“…The direct desulfurization pathway was inhibited, particularly by 2-MePIP. Kogan et al (444) compared the HDS of DBT with that of 4-MeDBT and 4,6-diMeDBT in the presence of PY and Q over sulfided CoMo/Al 2 O 3 catalyst. Kwak et al (443) investigated the effect of CAR and Q on the HDS of DBT, 4-MeDBT, and 4,6-diMeDBT over sulfided CoMo/Al 2 O 3 catalyst.…”

Section: E Furimsky and F E Massothmentioning

confidence: 99%

Hydrodenitrogenation of Petroleum

Furimsky¹,

2005

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A high level of hydrodenitrogenation (HDN) is required to achieve a desirable conversion of other hydroprocessing reactions. This results from a strong adsorption of nitrogen-containing compounds on catalytic sites that slows down the hydrogen activation process and hinders the adsorption of other reactants. Studies on model compounds and real feeds indicate that less than 50 ppm of nitrogen in the feed can poison catalytic sites. Kinetic studies determined adsorption constants of various nitrogen-containing compounds and concluded that at least four different catalytic sites are required to interpret experimental observations in contrast with a dual site site ffi concept, which only considered two sites. The advancements in experimental techniques allowed identification of products formed during very early stages of hydrodenitrogenation. These results confirmed that the removal of the amino group from saturated amines, as the last step in hydrodenitrogenation, is governed by the type of carbon to which the amino group is attached rather than the number of hydrogen atoms attached to carbon in a and b position to nitrogen Performance of conventional Co(Ni)Mo(W)/Al 2 O 3 catalysts during hydrodenitrogenation was enhanced by combination with various additives and by replacing the traditionally used g-Al 2 O 3 support with novel supports. Catalytic functionalities could be modified by using different precursors of active metals and varying conditions during preparation. Progress has been made in the development of catalysts possessing a high selectivity for hydrodenitrogenation. In this case, the nonconventional catalysts based on the carbides and nitrides of transition metals exhibited high activity and selectivity. Noble metal sulfides alone or supported on different supports were active for HDN as well. Feedstocks used for catalyst evaluation included model compounds and mixtures of model compounds as well as real feeds. The challenges in the development of catalysts for hydrodenitrogenation of heavy feeds containing asphaltenes and metals have been identified.In general, compared to Q, conversions were little affected by a methyl (Me) on the aromatic ring, while being lower for Me on the N-ring, except for 2-MeQ. It is evident that Me substitution in the 2-position had little effect on HDN over the NiMoP/Al 2 O 3 catalyst, whereas it actually enhanced the HDN rate over the CoMo/Al 2 O 3 catalyst. For both catalysts the HDN rate was suppressed in 6-MeQ and particularly in 3-MeQ and 4-MeQ. The distribution of N-containing intermediates was influenced by the ring substitution and the type of catalyst. This suggests that several factors influence the overall HDN mechanism of Qs. This should be kept in mind while analyzing differences in the networks proposed by different authors.The preceding discussion on the HDN of Q mostly referred to conventional catalysts. A number of studies on the HDN of Q were conducted over unconventional catalysts. For example, 3-and 4-MeQs were more reactive than Q over the unsupported Zr,...

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“…The rate constants of these two pathways were both about six times lower in the presence than in the absence of piperidine. This is different from the cases over metal sulfides [34][35][36] as well as over bulk Ni 2 P [10] and bulk MoP catalysts [11]. Over these catalysts, the HYD pathway of DBT was more strongly inhibited by nitrogen-containing compounds than the DDS pathway.…”

Section: The Inhibitory Effect Of Piperidinementioning

confidence: 61%