1076-61-5Relevant articles and documents
Promoted catalysts for hydrogenation of bicyclic aromatic hydrocarbons obtained in situ from molybdenum and tungsten carbonyls
Zakharyan,Onishchenko,Maksimov
, p. 22 - 31 (2018)
Promoted Мo and W catalysts have been prepared in situ via thermal decomposition of precursors, oil-soluble salts Mo(CO)6, W(CO)6, С°C16H30O4, and NiC16H30O4. TiO2, Al2O3, and ZrO(NO3)2 · 6H2O have been used as the acidic additives. Also, Mo and W unsupported sulfide catalysts have been prepared in the presence of elemental sulfur as the sulfiding agent. The catalysts have been characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. The activity of the catalysts prepared in situ has been evaluated in the hydrogenation reaction of bicyclic aromatic hydrocarbons by the example of model mixtures of 10% solutions of naphthalenes (unsubstituted naphthalene, 1- and 2-methylnaphthalenes, and 1,5- and 2,3-dimethylnaphthalenes) in n-hexadecane. The effect of the precursor/acidic oxide ratio on the activity of the formed catalyst has been found. Hydrogenation of bicyclic aromatic hydrocarbons has been conducted at a hydrogen pressure of 2 and 5 MPa and a temperature of 380 and 400°C for 2 h. Hydrogenation of the unsubstituted aromatic ring has been preferable due to the absence of steric hindrances. The degree of conversion of n-hexadecane under the reaction conditions has been 1.5–7.5% depending on the reaction temperature. It has been found that the activity of the sulfided catalyst in the conversion of 1- and 2-methylnaphthalenes is inferior to the activity of the unsulfided analogue, while partial replacement of TiO2 by Al2O3 results in a decrease in the conversion of the substrates as opposed to the unsulfided catalysts, in which the use of nanocrystalline Al2O3 promotes an increase in the conversion.
Nickel-tungsten sulfide aromatic hydrocarbon hydrogenation catalysts synthesized in situ in a hydrocarbon medium
Sizova,Serdyukov,Maksimov
, p. 470 - 480 (2015/11/23)
Nickel-tungsten sulfide nanocatalysts for the hydrogenation of aromatic hydrocarbons (HCs) have been prepared by the in situ decomposition of a nickel thiotungstate precursor in a HC feedstock using 1-butyl-1-methylpiperidinium nickel thiotungstate complex [BMPip]2Ni[WS4]2 as the precursor. The in situ synthesized particles have been characterized by X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy. It has been shown that the resulting Ni-W-S particles are nanoplates associated in multilayer agglomerates; the average length of the Ni-W-S particles is 6 nm; the average number of layers in the multilayer packaging is three. The catalytic activity of the synthesized catalysts has been studied in the hydrogenation of model mixtures of mono- and bicyclic aromatic HCs and in the conversion of dibenzothiophene in a batch reactor at a temperature of 350°C and a hydrogen pressure of 5.0 MPa. It has been shown that the studied catalysts can be used for the hydrofining of light cycle oil.
Reduction of Polycyclic Arenes by BH-Boranes, II Borane Catalyzed Hydrogenation of Naphthalenes to Tetralins
Yalpani, Mohamed,Lunow, Thomas,Koester, Roland
, p. 687 - 694 (2007/10/02)
Tetrapropyldiborane(6) (TPDB) and triethylborane (TEB) catalyze the regioselective and partial hydrogenation of naphthalene (N) and a number of substituted naphthalenes at 170 deg C to 200 deg C and hydrogen pressures of 25-100 bar.Tetralin (T) is formed quantitatively.Naphthalene derivatives are mainly hydrogenated in the least substituted ring.In the case of alkyl substituents, Lewis acid catalyzed migration and, to a lesser extent C-C bond rupture, lower the yield of the main tetralin derivative.Chlorinated naphthalenes and at the O-atom derivatized naphthols undergo also partial loss of the chloro or oxygen functional groups.The i nitially added borane acts only as a precatalyst and its slowly converted to catalytically active polyboranes of as yet unknown structures.Keywords: Hydroboranes/ Hydrogenation/ Naphthalenes/ Tetralins