1076-61-5Relevant academic research and scientific papers
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.
Synthesis of nickel-tungsten sulfide hydrodearomatization catalysts by the decomposition of oil-soluble precursors
Sizova,Kulikov,Onishchenko,Serdyukov,Maksimov
, p. 44 - 50 (2016/02/03)
Nickel-tungsten sulfide catalysts for the hydrogenation of aromatic hydrocarbons have been prepared by the in situ decomposition of an oil-soluble tungsten hexacarbonyl precursor in a hydrocarbon feedstock using oil-soluble nickel salt nickel(II) 2-ethylhexanoate as a source of nickel. The in situ synthesized Ni-W-S catalyst has been characterized by X-ray photoelectron spectroscopy. The activity of the resulting catalysts has been studied in the hydrogenation of bicyclic aromatic hydrocarbons and dibenzothiophene conversion in a batch reactor at a temperature of 350°C and a hydrogen pressure of 5.0 MPa. It has been shown that the optimum W: Ni molar ratio is 1: 2. Using the example of the hydrofining of feedstock with high sulfur and aromatics contents, it has been shown that the synthesized catalyst exhibits high activity in the hydrogenation of aromatic hydrocarbons.
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.
Characterization of New Methyl-Substituted Tetralins and Indans by 13C NMR Spectroscopy
Laurens, T.,Schmit-Quiles, F.,Nicole, D.
, p. 523 - 528 (2007/10/02)
In order to perform the analysis of the components contained in fossil fuels, carbon assignments of new methylated derivatives of tetralin and indan were obtained.Their chemical shifts were calculated by applying additivity rules. - Keywords: NMR; 13C NMR; tetralins; indans
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
Substituted 1,2,3,4-Tetrahydroaminonaphthols: Antihypertensive Agents, Calcium Channel Blockers, and Adrenergic Receptor Blockers with Catecholamine-Depleting Effects
Atwal, Karnail S.,O'Reilly, Brian C.,Ruby, Eric P.,Turk, Chester F.,Aberg, Gunnar,et al.
, p. 627 - 635 (2007/10/02)
Substituted 1,2,3,4-tetrahydroaminonaphthols were found to be calcium channel blockers with antihypertensive properties.These compounds also possessed adrenergic β-receptor blocking activity.From the structure-activity studies, no clear correlation emerged between the in vitro calcium channel blocking activity and the acute antihypertensive activity in cannulated spontaneously hypertensive rats.Extensive pharmacological testing of selected compounds indicated that aminonaphthols are antihypertensive agents with many pharmacological properties.The relative contribution of various pharmacological actions toward the observed antihypertensive activity is unclear.Since the clinically useful calcium channel blocker verapamil is structurally related to these compounds, one of the aminonaphthols, trans-3--1,2,3,4-tetrahydro-6,7-dimethoxy-2-naphthalenol (12), was compared with verapamil for calcium channel blocking activity, adrenergic blocking activity, and catecholamine-depleting activity.Both compopunds were found to be equipotent in these test systems.
