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Trimetallic NiMoW/Al2O3 catalysts based on mixed H4[SiMonWn-12O40] (n = 1, 3, 6, and 9) Keggin-type heteropolyacids (HPAs) were synthesized by incipient wetness impregnation of alumina with aqueous solutions of mixed HPAs. For comparison purposes, trimetallic samples were prepared from a mixture of monometallic H4[SiMo12O40] and H4[SiW12O40 ] HPAs with a Mo/W ratio corresponding to the mixed MoW HPAs. The catalysts were sulfided by a liquid phase method and tested in the model reactions of dibenzothiophene hydrodesulfurization and naphthalene hydrogenation, with subsequent addition of quinoline to study the effect of inhibition of target reactions. Further, the catalysts were tested in the hydrotreating of straight-run gas oil to evaluate the efficiency of catalysts on real feedstocks. In order to link catalytic performances with the preparation method and Mo/W ratio, the catalysts were fully characterized by high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, high-angle annular dark-field imaging, and quick X-ray absorption spectroscopy. It was found that the Mo/W atomic ratio of the structure-forming metals in the active phase, deriving from the Mo/W ratio in the HPA precursor, directly affects the ratio of the hydrogenation and hydrodesulfurization performances. For feedstock with a high concentration of N-containing compounds, it is necessary to use mixed NiMoW systems with a high tungsten percentage to reduce the inhibitory effect and ensure the quality of the products. The use of new mixed MoW Keggin HPAs has made it possible to enhance the synergistic effect in trimetallic NiMoW catalysts due to the closer interaction between Mo and W, which increased the sulfidation degree of metals and also contributed to the formation of highly active mixed NiMoWS sites.

A new method for the synthesis of 4-chlorononafluoro- and 4-bromononafluorobiphenyl by the reactions of nonafluorobiphenyl-4-thiol with Cl2, PCl5, and Br2, as well as of 4,4′-dichlorooctafluorobiphenyl from octafluorobiphenyl-4,4′-dithiol, 4′-chlorooctafluorobiphenyl-4-thiol, Cl2, and PCl5 was developed. 4-Bromo-4′-chlorooctafluorobiphenyl was synthesized for the first time from 4′-chlorooctafluorobiphenyl-4-thiol and Br2. 4,4′-Dichlorooctafluorobiphenyl was obtained as the main product in the reaction of 4′-bromooctafluorobiphenyl-4-thiol with PCl5.

A new method for the preparation of 2,3,4,5-tetrafluorophenol from 2-[(2,3,4,5,6-pentafluorophenyl)thio]acetic acid has been proposed. It included the intramolecular cyclization of the salt of this acid in the presence of K2CO3 with the substitution of the ortho fluorine atom and the formation of a lactone, which under the reaction conditions underwent the ring-opening with the formation of the potassium salt of 2-[6-hydroxy(2,3,4,5-tetrafluorophenyl)-thio]acetic acid. The resulting salt was converted into methyl ester and desulfurized with Raney nickel to 2,3,4,5-tetrafluorophenol. The proposed method is a simple and efficient way to obtain poorly available 2,3,4,5-tetrafluorophenol in ∼58% total yield based on 2-[(2,3,4,5,6-pentafluorophenyl)thio]acetic acid.

The major trends in the development of grease products are described in an analysis of the relevant research and patent literature, including research on superalkaline calcium greases for heavilyloaded friction units and possible applications of nanoparticle additives to multifunctional greases. Developments in lowtemperature greases derived from biodegradable polyester bases and lubricants for electric car friction units are also examined.

State of the art in the field of using biodegradable lubricating materials is considered, and data on recent achievements in their use are summarized. The major factors influencing the progress of studies in this field are associated with the environmental regulations becoming more and more stringent. Along with the use of poly(alkylene glycol) and ester liquids, raw materials of vegetable origin attract considerable interest of researchers developing biodegradable oils; cellulose can be used as a promising thickener for multipurpose lubricants.

Based on the analysis of scientific, technical, and patent literature, the main directions of the development of greases are described: super-alkaline calcium greases for highly loaded friction units, research into the possibilities of nanosized particles as additives to multifunctional greases, and the production of low-temperature greases on biodegradable polyester bases.

Supported and unsupported (with or without Co and Ni promotors) MoS2-based catalysts were prepared using conventional incipient wetness impregnation method on pure and carbonized alumina with an appropriate aqueous solution of a 12-molybdophosphoric heteropolyacid and cobalt or nickel citrate. Unsupported MoS2 catalysts were synthesized by leaching away the supports from MoS2/Al2O3, MoS2/C/Al2O3 and using industrial CoMo/Al2O3 catalyst (named as Et-MoS2-Ind) with HF acid. Catalysts were investigated by low-temperature nitrogen adsorption and transmission electron microscopy techniques to characterize their structure and morphology. Catalysts were tested in hydrodeoxygenation (HDO) of oleic acid (OA) in an autoclave under hydrogen pressure. CoMoS2/Al2O3, NiMoS2/Al2O3, and Et-MoS2-Ind catalysts were also investigated as single and dual catalytic systems, using a bench-scale flow reactor in co-hydroprocessing of mixed feed, containing straight-run gas oil and 15 wt. % of waste sunflower oil. The results of the catalyst tests show that hydrogenation/decarbonylation (HYD/DEC) selectivity in oleic acid HDO strongly depends on catalyst type. The CoMoS2/C/Al2O3 and CoMoS2/Al2O3 catalysts show low HYD/(HYD + DEC) selectivity, equal to 0.55. Unpromoted MoS2/C/Al2O3, MoS2/Al2O3, Et-MoS2-Ind and Ref-MoS2 samples have quite similar HYD/(HYD + DEC) selectivity around 0.85. The highest HYD/(HYD + DEC) selectivity (0.95) was reached over Et-MoS2/C and Et-MoS2 samples, which indicated that HDO had gone through HYD route without any formation of CO and CO2. A double-bed catalyst reactor comprising of the upper-layer bulk Et-MoS2-Ind and the under-layer Co(Ni)–MoS2/Al2O3 catalysts are proposed for the effective co-hydroprocessing of diesel and vegetable oil.

Pyrolysis of a mixture of 2,5-difluoro-3,4,6-trichlorobenzenethiol with tetrafluoroethylene leads to 2,2,3,3,4,7-hexafluoro-5,6-dichloro-2,3-dihydrobenzo[b]thiophene (the major reaction product) along with 2,2,3,3,4,6-hexafluoro-5,7-dichloro-2,3-dihydrobenzo[b]thiophene. Schemes of their formation with the participation of intermediate radicals are proposed. Oxidation of a mixture of the synthesized compounds gave 2,2,3,3,4,7-hexafluoro-5,6-dichloro-2,3-dihydrobenzo[b]sulfane-1,1-dioxide and 2,2,3,3,4,6-hexafluoro-5,7-dichloro-2,3-dihydrobenzo[b]sulfane-1,1-dioxide.

Methods for enhanced solvent dewaxing, among which the use of modifying additives is promising and inexpensive, are presented. Modifying additives belonging to various chemical classes are described. Polymer compositions based on poly(meth)acrylates with 10-30 C atoms in the alkyl radical are currently the most interesting modifying additives. Use of this type of compounds in solvent dewaxing significantly increases the filtration rate of the feedstock suspension. This affects the increase in plant productivity. At the same time, the yield of dewaxed oil increases by an average of 5% and the oil content in the paraffin slop wax/petrolatum decreases.

The non-catalytic hydrovisbreaking of straight-run mazut residue in an upflow reactor filled with inert turbulizer-packing having a cellular structure and a free volume of about 65% was investigated. Feedstock conversion of 55.1 % was obtained under moderate conditions for such a process (temperature 450°C, hydrogen pressure 5 MPa). The conversion of the non-volatile residue, boiling above 540°C, amounted to 90 % with 96 % demetallization and up to 76% conversion of asphaltenes and tars.. The main product of the hydrovisbreaking process was a kerosene—gasoil fraction with a yield of 43.6%. The distillate products of hydrovisbreaking were similar in quality to the distillates of a slow coking process, except for the lower sulfur content and the complete absence of silicon. The unconverted residue obtained after removal of the light distillates at atmospheric pressure had low viscosity and a low pour point. It can be used as feedstock in hydro purification for marine fuel production.

Bimetallic catalysts MoW/СОK-12 are synthesized on the basis of mesostructured silicate COK‑12 prepared from sodium silicate aqueous solution using the Keggin structure hetero polyacid H4Si-Mo3W9O40 as an oxide precursor of the sulfide active phase and with the use of the mechanical mixture of two monometallic hetero polyacids (H4SiMo12O40 and H4SiW12O40) at a molar ratio of Mo/W = 3/9. Alumina-based analogs with the same surface metal content are used as reference samples. The test samples are analyzed by low-temperature nitrogen adsorption and high-resolution transmission electron microscopy. The catalytic activity is studied in the combined hydrotreatment of dibenzothiophene and naphthalene and in the hydrodesulfurization of 4,6-dimethyldibenzothiophene in a flow unit. It is shown that the use of mesostructured silicate COK-12 as a support leads to an increase in catalytic activity in target hydrotreating reactions.

As- and Cl-containing impurities are highly detrimental to sulfided catalysts in hydrotreating processes. To prevent the irreversible loss of activity of the main sulfide catalysts by As and Cl contaminants, a protective double-layered guard bed catalyst is applied. Two types of mesoporous silica supports (SBA-15 and MCF) were used to obtain sorption-catalytic materials. The high specific surface area of the supports allowed for a significant increase in access to the active catalyst centers. The NiMo/SBA-15/Al2O3 and NiMg/MCF/Al2O3 sorption-catalytic materials demonstrated high activity and stability over 48 h for the simultaneous removal of As and Cl. The catalytic materials allowed for reducing the concentrations of As and Cl to less than 0.1 ppm in the diesel fraction under the following conditions: 5.0 MPa pressure, 2.0 h-1 LHSV, 300 L/L H2-to-substrate volume ratio, and 360 °C.

Furfural derivatives prepared from vegetable raw materials have recently become popular as high-performance fuel additives. Furfural oxygenates are particularly of interest. A lot of research has been devoted to preparing new materials from furfural, however, there is much to be discovered about their effect on physicochemical properties of fuels. The possibility of using furfural derivatives, obtained by their hydrogenation on copper and nickel catalysts with full conversion of furfural, as additives to fuel is considered in this article. Their impact on antiknock properties and chemical stability is evaluated. It has been found that futons are mostly effective in low-octane hydrocarbon bases, such as hydrocracking gasoline, at a concentration of 5-30 wt. %. A high concentration of potential resins can lead to the formation of deposits in the combustion chamber of the engine, which, in turn, requires additional research.

A method for the preparation of furfural dibutyl and diamyl acetals in a flow-through laboratory apparatus is recommended. Cetane numbers of compositions with butanol and dicumyl peroxide additives are determined, as well as low-temperature properties and sedimentation stability of diesel fuels with 3 wt.% acetals. Lubricating properties of the studied acetals were evaluated, and wear spot diameter values were determined.

This paper presents the results of testing a catalyst system developed for the demetallization and desulfurization of vacuum gas oil and heavy coker gas oil mixture at a pressure of 6 MPa, a temperature of 360-370°C, and a feed volumetric rate of 1 h-1 for obtaining a product having a sulfur content of 0.05 wt.%. The composition of RMB 30 marine fuel is developed with the application of a distillate fraction obtained from secondary processes and a depressant-dispersant additive in order to bring the pour point to the requirements of GOST32510-2013.

A bulk MoWS2 catalyst has been synthesized by acid etching of the carrier from the supported MoWS2/Al2O3 catalyst obtained on the basis of the mixed bimetallic heteropoly acid (HPA) H4[SiMo3W9O40]. As reference samples, monometallic MoS2 and WS2 catalysts have been prepared from the corresponding supported analogues, as well as a Mo + WS2 sample based on a mechanical mixture of monometallic HPA in the atomic ratio of Mo/W = 1/3. The catalytic properties of the synthesized catalysts have been studied in model reactions of hydrodesulfurization (HDS) of dibenzthiophene (DBT) and hydrogenation (HYD) of naphthalene in a flow unit. It has been shown that the catalytic activity of the samples in both the DBT HDS and naphthalene HYD reactions increases in the following order: MoS2 < WS2 < Mo + WS2$$ \ll $$ MoWS2. It has been found that the bulk tungsten-containing catalysts exhibit higher specific catalytic activity than the supported counterparts. Increased values of hydrogen uptake according to the results of hydrogen temperature-programmed reduction for the bulk catalysts indicate an increase in the number of active sites and the formation of a more effective active phase compared to supported catalysts.

Trimetallic NiCoMo catalysts supported on γ-alumina (γ-Al2O3), amorphous silicon dioxide (SiO2), and mesostructured silicate (SBA-15) with equal surface concentration of active components were synthesized, and their physicochemical characteristics, including the morphology of the active phase particles, were studied. The performance of the synthesized catalysts in target hydrotreating reactions at different concentrations of an organic nitrogen-containing inhibitor, quinoline (0–1000 ppmw nitrogen), was determined. The inhibiting effect of quinoline on the hydrodesulfurization and hydrogenation reactions occurring on the synthesized catalysts and the influence of the kind and properties of the support on this effect were evaluated.

The supported CoMoS2/Al2O3 and NiMoS2/Al2O3 catalysts were prepared by impregnating of alumina to incipient wetness with aqueous solutions of 12-molybdophosphoric heteropoly acid and nickel or cobalt citrates. A bulk Ref-MoS2 catalyst was obtained by thermal decomposition of ammonium tetratiomolybdate. The synthesized catalysts were investigated by low temperature nitrogen adsorption and high resolution transmission electron microscopy. The catalytic properties were studied in the dibenzothiophene hydrodesulfurization and naphthalene hydrogenation in the presence of dodecanoic acid or guaiacol in a flow unit with a microreactor under hydrogen pressure. It was shown that the bulk catalyst Ref-MoS2 has minimal sensitivity to dodecanoic acid and guaiacol during the combined hydrotreatment of dibenzothiophene and naphthalene. The effective adsorption constants of dodecanoic acid and guaiacol were calculated using the Langmuir—Hinshelwood model.

Mo(W)/SBA-15 catalysts are prepared using heteropoly acids H4SiMo12O40, H4SiW12O40, and H4SiMo3W9O40. The catalysts in the sulfide form are studied by low-temperature nitrogen adsorption, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. Catalytic properties are tested in the hydrodesulfurization of 4,6-dimethyldibenzothiophene. It is shown that the gas-phase sulfiding of Mo(W)/SBA-15 catalysts leads to increase in the average length of particles and the number of Mo(W)S2 layers in active phase particles compared with liquid-phase sulfiding with the use of dimethyl sulfide. The replacement of a quarter of tungsten atoms with molybdenum ones makes it possible to considerably improve the catalytic activity of the mixed catalyst Mo + W/SBA-15 compared with the monometallic counterparts. This effect can be enhanced due to the use of mixed heteropoly acid H4SiMo3W9O40 as a precursor of the active phase of the MoW/SBA-15 catalyst, which is apparently associated with the formation of MoWS2 active sites.

Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene has been synthesized as the major product of co-pyrolysis of 6-bromo-, 6-chlorooctafluoroindane-5-thiols, or bis(6-bromo-5-perfluoroindanyl)disulfane with tetrafluoroethylene under flow conditions at 400-625oC, along with small amount of tetradecafluoro-1,2,3,5,6,7-hexahydro-s-indacene. Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene formed in the reaction of 6-(meth-ylsulfanyl)octafluoroindane-5-thiol with tetrafluoroethylene at 420oC has been isolated, and its structure has been confirmed by X-ray diffraction analysis. The schemes of the products formation involving intermediate radicals have been proposed.

International audience; A series of unsupported mono- and bimetallic MonW12-nS2 catalysts were synthesized by alumina elimination from supported MonW12-nS2/Al2O3 samples using acid etching. Alumina supported catalysts have been in turn prepared by using monometallic H4SiMo12O40 and H4SiW12O40 heteropolyacids (HPAs), their mixture with Mo/W atomic ratio equal to 1/11 and 3/9, and mixed bimetallic H4SiMo1W11O40 and H4SiMo3W9O40 HPAs. All catalysts were characterized by N2 adsorption, temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), time-of-flight secondary ion mass spectrometry (ToF-SIMS), extended X-ray absorption fine structure (EXAFS) spectroscopy and powder X-ray diffraction (XRD) and their performance were evaluated in simultaneous hydrodesulfurization (HDS) of dibenzothiophene (DBT) and hydrogenation (HYD) of naphthalene. The etching process led to a successful removal of all the support and of the partially sulfided species, with sulfidation degrees of both Mo and W above 90 % on the final bulk solids. The active phase also underwent a rearrangement, as higher average length and stacking were measured on the bulk catalysts than on the original supported ones. Mixed MoWS2 phase was evidenced in all solids, prepared from mixed HPAs (MonW12-nS2) or from the mixture of monometallic HPAs (RefMonW12-nS2), by EXAFS and ToF-SIMS, with however a larger quantity on the MoW solids. It seems that the mixed MoWS2 phase observed on the supported MoW catalysts is maintained through the etching process, while on RefMonW12-nS2 the mixed phase, observed in a much lesser extent in the corresponding supported catalyst, could result from the aggregation of the monometallic slabs. MonW12-nS2 catalysts were found more effective than the monometallic catalysts and than the corresponding RefMonW12-nS2, in both dibenzothiophene hydrodesulfurization and naphthalene hydrogenation, which was related to the presence of the mixed phase maintained through the etching of the support.