A new method for the preparation of hydrodesulfurization catalysts based on the mechanochemical treatment of molybdenum under cryogenic conditions was proposed. The results of direct one-stage mechanochemical grinding of molybdenum at 77 K in gaseous media of He and H2 and in liquid N2, as well as in the presence of solid Ar, are reported. The physicochemical properties of the cryopowders and their catalytic activity in the model hydrodesulfurization reactions of dibenzothiophene and diesel fraction were examined.

Novel bulk single-component sulfide catalysts were prepared under the conditions of solid-phase dispersion of МoS2 molybdenite at various mechanical treatment times and various amounts of polar and nonpolar liquid microadditives. The chemical degradation of the samples in the air was found to lead to the formation of surface sulfate anions that shield catalytically active Mo sites. Indirect correlations of the hydrodesulfurization ability of MoS2 powders with the concentration of sulfate anions on their surface, and with the aqueous pH in the powder suspensions, including the dielectric permittivity of the organic dopants, can serve as reference indicators of high catalytic activity in the model reaction of dibenzothiophene hydrogenolysis. The study identified the most active sample able to run for an extended time during multiple cycles without losing its catalytic properties. Also, the paper discusses the dibenzothiophene conversion routes, the product composition, the probable structure of active sites in the catalysts, and the desulfurization degree of diesel fuel components.

The grinding of molybdenite as a dimensional precursor of the active component of a bulk hydrodesulfurization catalyst under cryogenic conditions in solid argon and liquid nitrogen is performed for the first time. The physicochemical properties of the samples are determined using instrumental methods. The chemical testing of their surface properties is carried out. The hydrodesulfurization ability of cryo-powders in the model reaction of dibenzothiophene is determined.

The milling of molybdenite under cryogenic conditions in argon has been performed for the first time, and the physicochemical properties of its samples, their catalytic activity in model reactions of hydrodesulfurization of dibenzothiophene and diesel components, and the ability to initiate the isopropylbenzene oxidation reaction have been studied. The samples have been found to exhibit high catalytic activity.

The paper deals with the solid-phase method for producing bulk two-component sulphide catalysts by the mechanochemical coupling of commercial molybdenum, cobalt, and nickel powders. The research presents physicochemical properties of the catalysts and discusses the activity of the latter in model reactions of dibenzothiophene and 4,6-dimethyldibenzothiophene hydrodesulphurisation including the latter in the presence of carbazole and phenanthrene, and also upon the hydrotreatment of sulphur components in diesel fraction.

Hydrodesulfurization catalysts are prepared via mechanical grinding of molybdenite under cryogenic conditions (80 K). Cryo-catalysts are characterized by X-ray phase analysis, X-ray photoelectron spectroscopy, and sedimentation analysis. The catalytic activity of the obtained cryo-samples is studied in a model hydrodesulfuration reaction of dibenzothiophene and in the course of hydrogenolysis of the components of the diesel fraction. It is shown that the activation of cryo-catalysts does not require the use of any sulfur-containing reagents.

— More than 70% of the world’s reserves of hydrocarbons is in the form of heavy petroleum feedstocks. Increasing the efficiency and depth of processing of such feedstocks is an important problem of petroleum refining. Cobalt powders and their catalysts prepared in a single stage are tested for the first time in the cracking process at the Novokuibyshevsk petroleum refinery. The composition and properties of the samples are studied via X-ray phase analysis, scanning electron microscopy, and temperature-programmed reduction. Surfaces of cobalt contains oxygen in Co 3 O 4 and CoO inside layers, while mechanoactivation redistributes some of these oxides and alters the composition of products of tar cracking. Cobalt has more catalytic activity in the cracking of tar after mechanoactivation than the original powder. The yield of light fractions is 70% with mechanically activated cobalt, 10 wt % higher than without mechanoactivation, and 25% higher than with no cobalt powders.

Russia occupies the third place in the world in terms of stocks of heavy oil raw materials. The development of deposits of light and medium oils makes it inevitable to involve heavy, as well as residual, petroleum raw materials in processing to meet the growing demand for petroleum products. Increase of the depth of oil processing possible in various ways, one of which is the use of new efficient catalysts, resistant to corrosion, poisoning and coking. Tungsten carbide, meeting these requirements, is a promising starting compound for the production of cracking catalysts for heavy oil feedstocks. The influence of tungsten carbide and its calcination temperature on the composition and yield of oil paraffin cracking products on the resulting catalysts was studied to investigate its catalytic activity, the optimum treatment temperature of tungsten carbide was determined. The high catalytic activity of a WC sample calcined at 420 degrees C is shown. Using the physicochemical methods of investigation, the properties of tungsten carbide samples, as well as the composition and properties of the paraffin cracking products in the presence of the catalysts obtained, were studied.

The ability to modulate the life process of stem cells conjugated with MNPs via a magnetic field is promising as multifunctional tool in biomedicine. Experiment on mice demonstrates the high accumulation of iron ions measured via stripping voltammetry in the bone marrow in respect to bone, liver or kidney. Therefore, the potential cytotoxic effects of iron oxide magnetic nanoparticles (MNPs) on bone marrow cells become more predictable in comparison with the other examined cells. This study examined in vitro responses of mouse bone marrow-derived granulocyte-macrophage committed stem cells (colony-forming units of granulocytes and macrophages, CFU-GM) to a controlled amount of MNPs prepared by the exploding wire method; and to a moderate static magnetic field (SMF) of about 160 Oe. The moderate SMF did not affect CFU-GM capacity. Two different regimes of bone marrow cells cultivation with MNPs were investigated. Remarkably, adding MNPs to cells either decreased (1st cultivation regime, 6 pg MNPs per 1 cell) or enhanced (2nd regime, 20 pg MNPs per 1 cell) the colony-forming activity of CFU-GM, depending on the regimes of cultivation. The action of a moderate SMF on cells cultivated with MNPs inverts their effects on stem cell colony formation. Possible mechanisms of these phenomena are discussed. The main pathway was explained by a change in the presence of iron, either inside or outside of the cell, following the formation of free radicals susceptible to SMFs. Nanoscale magnetite activity within the pool of bipotent hemopoietic stem cells supports its proposed usage as supplement in cell technologies, theranostics, bone marrow repair and regenerative medicine. Further study is necessary to examine the intra-and intercellular mechanisms of the SMF's modulating effect on stem cell activity caused by magnetite MNPs. (C) 2017 Elsevier B.V. All rights reserved.

The relevance of the research is related to the need to develop effective methods of processing heavy hydrocarbon feedstocks. Conventional light crude oil is only about 25 % of proven global oil reserves, and the rest are heavy and extra A heavy oil, bitumen. Furthermore, there is the problem of processing heavy residual oil fractions. In Russia only the Omsk oil refinery provides the depth of oil processing more than 90 %. The high content of heteroatomic compounds in heavy oil feedstock and its propensity for high coke formation lead to deactivation of catalysts used, which means that a catalyst that is stable to coking and poisoning is necessary for efficient processing of heavy oil feedstock and residual fractions. The main aim of the work is to study the catalytic activity of micron sized tungsten carbide powder in cracking goudron of Novokui-byshevsk oil refinery. The methods used in the study: scanning electron microscopy, energy A dispersive X-ray spectroscopy, X-ray diffraction, differential scanning calorimetry - thermogravimetry, gas chromatography, elemental analysis, X-ray fluorescence analysis The results. The authors have studied the effect of time and temperature on thermal cracking of goudron of Novokuibyshevsk oil refinery and determined the optimal conditions for its experimental processing. The influence of tungsten carbide amount on composition of cracking products was studied. It was found that the micron A sized tungsten carbide powder possesses a catalytic activity in a heavy hydrocarbon cracking reaction and makes it possible to increase the yield of light fractions up to 70 % by weight. Reused tungsten car A bide powder retains catalytic activity during three cycles of usage. The individual composition of the gasoline fractions of cracking pro A ducts in the presence of tungsten carbide powders was studied.

The paper presents the results of experimental studies of massive sulfide catalysts by simultaneous thermal analysis and mass spectrometry. It is found that the STA/MS methods are quite informative for testing the catalyst systems based on MoS2 and are useful in identification of the reference features that could be used to predict their activity. It is also shown that the defect structure of molybdenum disulfide formed during mechanical activation is reflected on the DSC curves.

Впервые обнаружена способность нанопорошков металлов влиять на устойчивость гидрофобных эмульсий. Найден нанореагент, который по эффективности не уступает высокоэффективным неионогенным деэмульгаторам и обладает уникальной способностью – легко отделяется и сохраняет свою эффективность при многократном его использовании. Обсуждены механизмы процесса.

Metal nanopowders were found to affect the stability of hydrophobic emulsions. A nanoreagent as effective as highly nonionic demulsifiers was found. It can easily be separated and retains its efficiency after repeated use. The mechanisms of the process were discussed.

For the first time, an approach to a single-stage manufacture of bulky sulphide catalysts using a solid-phase method performed by means of the mechanical activation of a mixture consisting of coarse molybdenum disulphide and cobalt powders, in the presence of detonation nanodiamonds is described. An effect exerted by the mechanical treatment duration, ratio between the initial components and nanodiamonds on the process of nanofragmentation of molybdenum disulphide and activity of catalytic systems obtained in the model reaction of DBT hydrodesulphurisation has been studied.

Получены новые катализаторы гидроочистки на основе электровзрывных нанопорошков молибдена, никеля и нитрида алюминия. Исследованы их физико-химические свойства, показана возможность прямого сульфидирования нанопорошков молибдена сернистыми соединениями прямогонной дизельной фракции нефти. Установлена высокая гидродесульфирующая способность нанопорошковых катализаторов.

New hydrofining catalysts based on molybdenum, nickel, and aluminum nitride nanopowders produced by electrical explosion are obtained. Their physicochemical properties are studied. The direct sulfurizing of molybdenum nanopowders with sulfides from straight-run diesel oil fraction is shown to be possible. The high hydrodesulfurization capability of nanopowder catalysts is established.