Petroleum Chemistry (v.51, #5)

Fischer-tropsch iron catalysts supported on fibrous carbon material by A. Yu. Krylova; A. A. Panin; A. S. Lyadov; S. A. Sagitov; V. I. Kurkin; Yu. G. Kryazhev (317-323).
Iron catalysts supported on an activated fibrous carbon material (AFCM) and characterized by high performance in the hydrocarbon synthesis from CO and H2 have been studied. It has been shown that the promotion of Fe/AFCM catalysts with potassium and aluminum oxides or with copper reduces the optimum temperature of Fischer-Tropsch synthesis and enhances the polymerizing activity of the catalysts.

The molecular composition of hydrocarbons and heteroatomic compounds of the lube stock of Ivanovskoe asphaltite has been studied. The results obtained allow for the conclusion that the source material for the formation of the asphaltite deposit was crude oil generated in the catagenesis stages corresponding to the beginning of the main phase of oil generation by marine carbonates, whose sedimentation and diagenesis had occurred in coastal marine environments under anoxic conditions upon euxinia in the benthic zone. The asphaltite composition bears no signs of deep biochemical oxidation of the original oil.

Generation of C11–C17 monoalkyladamantanes via catalysis of some oxygen-containing precursors of petroleum hydrocarbons by Ch. M. Badmaev; M. V. Giruts; O. G. Erdnieva; V. N. Koshelev; G. N. Gordadze (331-335).
Oxygen-containing compounds that are known to be precursors of petroleum hydrocarbons have been subjected to catalysis on an aluminosilicate catalyst. It has been found for the first time that along with C11–C12 monoalkylated adamantanes, which are typically present in crude oils, the homologous series of 1- and 2-n-alkyladamantanes up to and including n-heptyladamantanes are generated via the catalysis (monoalkyl-substituted adamantanes with a substituent heavier than the ethyl radical have never been found in any crude oil). It has been shown that, with the increasing degree of conversion, C13–C17 adamantanes disappear and only 1- and 2-methyl- and ethyladamantanes remain in the catalyzates. The absence of high-molecular alkyladamantanes (C13 and higher) in crude oils is supposedly attributed to relatively high maturity of crude oil.

On the mechanism of catalytic conversion of fatty acids into hydrocarbons in the presence of palladium catalysts on alumina by A. S. Berenblyum; T. A. Podoplelova; R. S. Shamsiev; E. A. Katsman; V. Ya. Danyushevsky (336-341).
A conversion of stearic acid into hydrocarbons in the presence of palladium on alumina has been studied. It has been shown that heptadecane and carbon monoxide are formed as the main products, diheptadecylketone is formed as a by-product, and the contribution of the decarbonylation reaction increases as compared to decarboxylation in the presence of hydrogen with an increase in its pressure. The formation of heptadecene and formic acid as intermediate products has allowed the conclusion that the cleavage of the carbon-carbon bond in the stearic acid molecule R-COOH takes place in the Pd coordination sphere, resulting in the formation of formic acid (or its fragment associated with palladium) and the corresponding olefinic product. Depending on the reaction conditions, formic acid and/or its fragment decompose, yielding CO and H2O or CO2 and H2. The main routes of the reaction have been simulated using quantum-chemical methods, and it has been shown that the reaction rate-limiting stage is the cleavage of C-C bond in the acid molecule.

The joint inhibiting effect of heavy metal N,N-diethyldithiocarbamates M(dtc) n , where M = Cu(II), Co(III), or Pb(II), and three aromatic amines (1: 1) in the initiated oxidation of ethylbenzene with oxygen at 75°C has been examined. The synergistic inhibitory effect of 1: 1 M(dtc) n -amine pairs strongly depends on the nature of the metal atom and the chelate unit structure of the metal dithiocarbamate. For most couples, the formation of new Cu(II), Co(III), and Pb(II) complexes of the [M(dtc) n -amine] type in chloroform via coordination of the amine donor atom to the metal has been proved spectrophotometrically. Possible routes of oxidation chain termination by the newly formed complexes have been established.

Kinetic parameters of the reaction of isobornylphenols with peroxy radicals by L. I. Mazaletskaya; N. I. Sheludchenko; L. N. Shishkina; A. V. Kuchin; I. V. Fedorova; I. Yu. Chukicheva (348-353).
The stoichiometric factors of inhibition and the rate constants (k 7) were measured for the reaction of isobornylphenols with peroxy radicals of ethylbenzene. The values of k 7 of the compounds under study increase with an increase in the amount of alkyl substituents and OH groups on the aromatic ring. The introduction of the oxygen atom between the o-isobornyl substituent and the aromatic ring decreases k 7 by a factor of 6.5. The inhibiting action of binary mixtures of sterically hindered phenols with 2-isobornyl-4-methylphenol and 2,6-diisobornyl-4-methylphenol in the initiated oxidation of ethylbenzene is close to additive.

Modeling the octane numbers of alkenes by the inverse function method by A. N. Ryzhov; Yu. A. Strizhakova; E. A. Smolenskii; A. L. Lapidus (354-362).
On the basis of the octane-number topological equivalents (TEs) constructed earlier by the inverse function method, related to the octane numbers by a biunique function, and linearly dependent on the number of carbon atoms n for n-alkanes, the octane numbers of alkenes have been simulated with the use of optimal topological indices. The models obtained suggest the maximum attainable (within linear QSPR approaches) accuracy of calculation, which exceeds by a few orders of magnitude that of previously known procedures. The octane numbers are predicted for 68 alkenes that have not been characterized experimentally.

The mechanism of action of additives for diesel fuel is studied in terms of molecular interactions. Using UV spectrophotometry, electron microscopy, conductivity, and other methods, we give experimental evidence of these interactions in diesel, including in the presence of additives. It is shown for the first time that the efficiency of diesel additives depends on the formation of new structures, such as charge-transfer complexes. Based on the analysis of the chemical structure of various additives, we make a conclusion that they all are classified as surfactants. It is known that diesel fuels are disperse fuel systems. Therefore, the experimental data on decreasing surface tension at the interface of a disperse fuel system in the presence of additives indicate that the additives are fuel stabilizers. A conclusion is drawn that additives that differ in chemical structure and have different functional purposes, including multifunctional additives, operate in a fuel disperse system by a common mechanism that is similar to the action of surfactants in classical disperse systems. This mechanism is associated with an increase in the stability of a disperse fuel system in the presence of additives and, as a consequence, with an improvement in its quality.

One-step synthesis of alkyd resins in the presence of new sulfonated cation-exchange (nano)catalysts by A. G. Azizov; G. I. Amanullaeva; R. V. Alieva; N. R. Bektashi; S. F. Akhmedbekova; E. M. Garayeva (370-380).
A method for the one-step synthesis of alkyd resins based on glycerol, phthalic anhydride, and vegetable oils using new sulfonated cation-exchangers and Ti-containing metal-polymer nanocomposites as catalysts has been developed. The film-forming properties, composition, structure and molecular weight characteristics of the synthesized resins have been studied by IR, NMR spectroscopy, and gel chromatography. The possibilities of regulating the molecular-weight distribution of the obtained alkyd resins depending on the nature of the catalyst and the reaction conditions have been revealed.

Remediation of the damaged environment of oil-producing areas by L. K. Altunina; L. I. Svarovskaya; Yu. M. Polishchuk; O. S. Tokareva (381-385).
An integrated approach that includes physicochemical and microbiological methods has been proposed to form the basis for improvement of environmental conditions. The feasibility of assessing environmental risk by mapping the effects of air pollution on vegetation has been considered. The environmental risk has been assessed with allowance for the sensitivity of various plant communities to atmospheric pollution.

The kinetic behavior of sorption of petroleum and petroleum products from the water surface by polymeric sorbents based on a foamed polystyrene formula has been studied. It has been found that the sorbents have good sorption properties, high floatability, and hydrophobicity. The effect of the environmental temperature and the apparent density of the sorbents on their sorption properties in a medium of crude petroleum and petroleum products has been shown.

N-Alkenylammonium chlorides were synthesized from diethylamine, 4-chloropent-2-ene, and a mixture of 2-methyl-3-chlorobut-1-ene and 3-methyl-3-chlorobut-1-ene. The reaction conditions were optimized. The structure of the products was proved and the main physicochemical characteristics of the synthesized compounds were determined. The synthesized quaternary ammonium salts were tested for bactericidal activity towards corrosion-active microorganisms.