Description: In this study, a thermo-responsive temporary plugging agent was developed with the property of sol-gel-sol transition behavior at different temperatures. At low temperature, the material is in sol state, while increasing temperature led to a stable gel formation, but the gel can transform to sol again upon further heating. This unique behavior was characterized by a series of SEM, FT-IR, XRD, rheology and viscoelasticity measurements. All scientific results showed non-covalent interactions between the components, which play an important role for the supramolecular gel formation. These findings provide this system can be applied as temporary plugging agent by the idea of temperature-induced smart material with the specialty of cross-linker and gel-breaker free. Physical simulation experiment results showed that the material is good mobility liquid at room temperature. After injecting to formation, the fluid gradually transformed to hard gel around 90°C with sufficient strength to block cracks. Upon further heating by formation, the hard gel would collapse to sol around 110°C without adding additional gel breakers, leading to flowback sufficiently and low damage to fracture. This novel temporary plugging agent also has potential use in diverting fracturing, network fracturing, drilling, well completion, well clean etc.

Description: The genesis of higher alkyltoluenes with a normal alkyl chain ( n -ATs) has been studied. The conditions for their formation from both individual C 18 (oleic and stearic) fatty acids and C 14 alcohol in the thermocatalytic mode and from Tasmanites planktonic algae during noncatalytic thermal treatment have been considered. The feasibility of the formation of n -ATs has been confirmed by determining their composition and structure.

Description: 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°C 16 H 30 O 4 , and NiC 16 H 30 O 4 . TiO 2 , Al 2 O 3 , and ZrO(NO 3 ) 2 · 6H 2 O 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 TiO 2 by Al 2 O 3 results in a decrease in the conversion of the substrates as opposed to the unsulfided catalysts, in which the use of nanocrystalline Al 2 O 3 promotes an increase in the conversion.

Description: The kinetics of the pyrolysis of solid organic polymers by their heating with a gas or a metal melt have been studied. The design features of a small-sized pyrolysis unit for organic polymers have been determined. The pyrolysis process on this unit has been experimentally substantiated. The specifics of the processes of “conventional” pyrolysis in the gaseous heat carrier and the pyrolysis of organic polymers in a lead melt have been revealed. It has been shown that the resulting pyrolysis liquid can be used as a feedstock for the production of the expensive organic solvent limonene or synthetic oil similar in properties to domestic crude oil.

Description: The conversion of ethanol and fusel oils to a С 3 –С 12 alkane–aromatic fraction with high activity and selectivity in the presence of the Pd–Zn/TsVM pilot catalyst has been demonstrated. It has been shown that the ethanol conversion to alkanes and aromatic hydrocarbons in the presence of this catalyst proceeds by various routes to give ethylene and diethyl ether as intermediate products providing a 90–95% yield on the converted ethanol carbon basis for the target С 3 –С 12 fraction containing up to 40% of branched alkanes.

Description: Vulcanization, by creating a three-dimensional cross-linked network, improves the physicalmechanical and thermal properties of elastomers. A popular agent for curing natural rubber (NR) is sulfur. Insoluble sulfur (IS) and rhombic sulfur (RS) are common allotropes of elemental sulfur. In this research, it was observed that the use of the two types of sulfur (IS and RS) gives different results. In terms of cure behavior, tear resistance and hardness, RS-vulcanized NR performed better, whereas in viscosity, tensile strength, aging and compression set, IS-vulcanized NR was better; because of the lack of blooming, IS could replace of rhombic sulfur as the curing agent in certain applications.

Description: The effects of the H 2 /CO ratio, pressure, temperature, and the reaction-gas recycle ratio on the selectivity for hydrocarbons (HCs), including long-chain C 35+ HCs, in the Fischer–Tropsch synthesis over a supported industrial cobalt–silica gel catalyst have been studied. The synthesis parameters have been as follows: a pressure of 2.0 or 6.0 MPa, an H 2 /CO ratio of 1–5, a recycle ratio of 2–6, a temperature of 150–240°C, and a gas hourly space velocity of 1000 h −1 . It has been shown that gas recycling provides thermal stability in the catalyst bed, significantly increases the yield of C 35+ HCs, and makes it possible to control the group and fractional composition of the synthesis products.

Description: The interaction of ethylene glycol and glycerol with carbamide in the presence of nanosized cobalt oxide obtained by the decomposition of cobalt(II) acetylacetonate in diphenyl ether is studied. The average size of the nanosized catalyst particles is 8–10 nm. The effect of nanoheterogeneous catalysis on the cyclocondensation of polyatomic alcohols with carbamide is investigated. A high capacity of the nanosized catalyst in this process is found 150 g(cyclic carbonate)/(g(catalyst) h), which is more than 100 times higher than the capacity of conventional catalysts.

Description: The hydroconversion of high-sulfur oil shale in the presence of natural mineral matrices: shale ash, sandstone, and clay has been investigated. It has been shown that mineral matrices containing clays and iron exhibit catalytic activity during the hydroconversion of oil shales. Due to this activity, a significant reduction in the sulfur and nitrogen content and an increase in the amount of light fractions in the resulting synthetic oil are achieved.

Description: The hydrogenation of petroleum resins (PRs) in the presence of commercial NVS-A, GO-15K, AGKD-400, and AKM nickel–tungsten, cobalt–molybdenum, and nickel–molybdenum sulfide catalysts and sulfided palladium MA-15 has been studied. Features of changes in the average molecular mass ( M ) of the PRs in the presence and absence of sulfur compounds in the reaction medium have been determined. The highest degree of hydrogenation is achieved in dilute PR solutions with a concentration of 10–20%; an increase in the process temperature and pressure leads to an intensification of the polymer chain degradation reactions. Swelling of the polymer globules in “good” solvents (benzene, toluene) makes the polymer chains more accessible to the active sites of the catalyst and thereby leads to an intensification of both the hydrogenation and thermal degradation reactions. The process run without any solvent does not provide a sufficient degree of hydrogenation of aromatic moieties owing to the high viscosity of the reaction mass and the resulting high diffusion restrictions.