Vol 59, No Suppl 1 (2019)

New approaches to the formation of active, selective, and stable Ni, Co, and Ni–Co catalysts for partial oxidation and dry reforming of methane into synthesis gas (a mixture of hydrogen and carbon monoxide) are considered.

General features of the distribution of vanadium and nickel in the products of two-step solvent fractionation of asphaltenes have been using the exampley of heavy crude oils from various fields of the Volga–Urals oil-and-gas basin (Russia). At the first step, during the treatment of a solution of asphaltenes in toluene with an excess of n-hexane, vanadium and nickel are predominantly concentrated in the insoluble fraction that is characterized by increased molecular weight, aromaticity, and degree of condensation with a decreased fraction of heteroatomic sulfur- and oxygen-containing structures. At the second step, during the treatment of the solution of asphaltene fractions in toluene with an excess of dimethylformamide, characteristic features of the distribution of vanadium and nickel in the obtained fractions have been revealed for heavy oils from different fields. As a result, differences in the concentration of metal complexes of vanadyl with asphaltenes have been determined for the heavy oils from Carboniferous and Permian productive sediments.

A new method for plasma-assisted reforming of hydrocarbon gases is briefly described, and the results of oxidative (without the synthesis gas stage) and nonoxidative conversion to new gaseous and liquid products are exemplified. The method is based on the unique property of cold plasma, the dramatic acceleration of chemical processes due to the plasma activation of particles, which makes it possible to enhance reactions in small flow reactors without the use of catalysts.

Characteristics of zeolite ZSM-12 crystallization using methyltriethylammonium chloride and N,N-dimethyl-N-ethyl(monoethanol)ammonium bromide as templates have been studied. The materials have been characterized by X-ray diffraction analysis, scanning electron microscopy, X-ray fluorescence analysis, low-temperature nitrogen adsorption–desorption, temperature-programmed desorption of ammonia, and solid-state ²⁷Al nuclear magnetic resonance spectroscopy. It has been shown that dimethylethylethanolammonium bromide inhibits crystal growth along the a and c planes and thereby contributes to crystal growth only in the direction of the b axis, which, in turn, leads to lower surface area and acidity of the sample than the respective parameters of the zeolite synthesized using methyltriethylammonium chloride.

The activity of the catalyst systems of a number of diphosphine ligands and chromium complexes based on 1,2-bis(diphenylphosphino)benzene in the ethylene oligomerization reaction has been studied. Structural modifications of diphosphine ligands have been performed to create selective catalyst systems for ethylene oligomerization. It has been shown that the introduction of ortho-functional groups into one of the phenyl substituents at the phosphorus atom in diphosphine ligands makes it possible to carry out the process of ethylene oligomerization to 1-hexene with the selectivity of 90 wt % and above. One of the complexes (chromium complex 15) with a functionalized diphosphine ligand has been characterized by X-ray structure analysis. The influence of the change in the amount of the activator and its type on the activity of the catalyst systems has been studied. It has been shown that the replacement of some organoaluminum activator, methylaluminoxane, by trimethylaluminum does not decrease the productivity and selectivity of the catalyst systems based on diphosphine chromium complexes.

Effect of the textural characteristics of NaX-type zeolite catalysts in the cation-exchange form on the main indicators of isobutane alkylation with butylenes has been studied. The best activity and selectivity indicators are achieved at a total pore volume of 0.255–0.295 cm³/g, a specific surface area of the samples of no more than 470 m²/g, and a micro/mesopore volume ratio of 2.5–5.5. It has been found that a catalyst sample based on a zeolite pelletized without a binder has all optimum textural characteristics; it is the best sample in terms of alkylate yield (100 wt %), conversion (99 wt %), and alkylate quality (trimethylpentane (TMP) selectivity of 72.6 wt %, an amount of the fraction boiling above isooctanes (C₉₊) of 5.8 wt %).

The catalytic pyrolysis of lignin under microwave (MW) irradiation in the presence of iron-containing systems deposited directly on the lignin surface from various precursors has been studied using iron acetylacetonate, diacetylferrocene, and potassium trioxalatoferrate(III) as the precursors. The study has been focused on the effect of the argon eluent gas flow rate (300–60 mL/min) on the yield of the liquid product fraction. The effect of the gaseous medium (Ar, H₂/Ar, O₂/Ar) on the yield of liquid products formed by MW treatment has been studied. It has been shown that a maximum yield of liquid products is achieved in a medium of the inert gas argon or in a hydrogen/argon mixture (33 or 36%), whereas this yield in an oxygen/argon mixture is twofold lower (17%). The gas chromatography–mass spectrometry method has been used to determine the qualitative composition of the liquid product fraction, which is mostly represented by phenol and anisol, the derivatives of the monomeric units of lignin (coumaryl and coniferyl alcohols). In studying the effect of the iron precursor deposited on the lignin surface, it has been found that the liquid yield increases twofold from 18 to 36 or 34% in the presence of iron acetylacetonate Fe(C₅H₇O₂)₃ or potassium trioxalatoferrate K₃[Fe(C₂O₄)₃] ⋅ 3H₂O, respectively, at a feed gas flow rate of 300 mL/min and a temperature of 700°C.