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The studies with different amines aimed to select the most rational ones as the base of the mixture by the criteria of the maximum reaction temperature, the pH value of the resulting mixture of reaction products, its viscosity under equal conditions (ambient temperature T = 25°C), the molar ratio between the base and the acid in proportions of 1.2:1, the content of acetic acid in the mixture of acids of 40%, the content of solvents of 35% of the mass of the reacting mixture showed that N-butylamine meets all the criteria. It was suggested using it for further research in exothermic reactions in developing the technology for removing paraffin deposits. Experiments using N-butylamine as a base, solvents of kerosene and xylene with a total mass of 35%, an acidic composition of acetic acid (50%) and LAS (50%), with a molar ratio between base and acid of 1.2:1, the total volume of the reacting mixture of 400 ml showed that the composition of solvents with xylene content of 10% and kerosene of 90% has the best ability to dissolve paraffin deposits (88%) than in the absence of xylene (80%). This composition of solvents also has a better state of the reaction products than in the case of a xylene content of more than 20% (no layer is formed, ARPD is not re-formed). Therefore, the composition of solvents with 10% xylene and 90% kerosene is most optimal. [ABSTRACT FROM AUTHOR]

The article described the developed technology for the phased removal of asphalt, resin and paraffin deposits in tubing using physical and chemical effects on the gas-liquid flow by pumping a mixture of organic acid, organic amine and organic solvents and a mixture of polyvinyl acetate, organic solvents and an activator into the bottomhole formation zone. The use of these mixtures can increase the technological and economic efficiency of gas-lift wells. As a result of industrial testing of the technology for the phased removal of asphalt, resin and paraffin deposits in tubing by the thermochemical method and inhibition of the formation of paraffin deposits by pumping reagents into the bottomhole formation zone with their subsequent gradual removal, a 100% effect was achieved in two wells of the White Tiger field. [ABSTRACT FROM AUTHOR]

In this paper, one of the most important issues of oil production is considered - the prevention of the formation of asphalt-resin-paraffin deposits during the operation of wells. In the course of the study, the main chemical compositions currently used in the conditions of field development are considered. Each of the technologies is considered in detail and, based on the experience of using chemical compositions, a number of calculations are carried out, the final results of which make it possible to evaluate these agents in terms of performing specified functions. Thus, each of the compositions under consideration has significant ranges of parameter variation, which makes it possible to use them in difficult mining and geological conditions. The obtained conclusions make it possible to optimize the mechanism of selection of compositions for carrying out treatments. [ABSTRACT FROM AUTHOR]

Paraffin is considered the ideal candidate for latent heat storage material. However, there is a significant problem related to the mushy region that disrupts the heat transfer process and tends to have a high supercooling degree. High-density polyethylene (HDPE) promotes a stable phase transition for the paraffin during the melting/freezing process. Therefore, the present study evaluates the effect of adding HDPE at a different ratio to form composite paraffin to evaluate the supercooling degree of the composite. Four samples are prepared for the evaluation: pure paraffin and composite paraffin/HDPE at HDPE ratios of 5 wt%, 10 wt% and 15 wt%. The static charging/discharging test is performed to estimate the melting/freezing temperature of the sample. Compared to pure paraffin, there is a significant change in the composite's melting/freezing temperature, which implies the effect of HDPE on the sample. The lowest melting temperature occurs at composite with 5 wt% HDPE with a temperature of 58.4 °C. The lowest freezing temperature and supercooling degree are obtained by the sample with 15 wt% HDPE at 68.6 °C and 9.5 °C, respectively. Further observation by using a scanning electron microscope and Fourier transform infrared is discussed in detail within the article. [ABSTRACT FROM AUTHOR]

The domestic technology of olefin production is mainly organized by the method of dehydrogenation of paraffins in a fluidized bed on an alumochrome catalyst circulating in a reactor-regenerator system. Currently, the leading enterprises of the oil and gas industry producing olefin hydrocarbons are conducting a two-stage method of dehydrogenation of paraffin hydrocarbons. In this paper, the possibility of dehydrogenation of butane – isobutane-containing fractions without their preliminary separation on the surface of an alumochrome catalyst is studied. The activity of the catalyst for the release of olefins on the skipped paraffins was evaluated, as well as the selectivity of the process for the release of olefins on decomposed paraffins, taking into account the volumetric feed rate of raw materials at standard temperature conditions. As a result of the joint dehydrogenation of butane: isobutane in a threefold excess of n-butane, there is an increase in total activity and selectivity when testing pure n-butane separately. Improving the in dicators of the ODA process [ABSTRACT FROM AUTHOR]

In this article, the effect of temperature and reaction rate on a catalyst consisting of [(MoO3)x·(ZrO2)y·(ZnO)z/HSZ], which has high productivity, selectivity, stability, robustness, activity, low cost and minimal coking properties, was studied for the catalytic dehydroaromatization of methane. The effect of reaction duration on methane conversion and the yield of target products was studied. In the case of catalytic aromatization of methane, at temperatures of 650-700°C, the yield of aromatic hydrocarbons is small, with methane conversion reaching the highest value 120 minutes after the start of the reaction. At 750 ℃, the highest conversion of methane is observed at 390 minutes of reaction. At 360 minutes of reaction between 650-750 ℃, aromatic hydrocarbons are formed in the highest yield. Over time, the decrease in the total conversion of methane is explained by the formation of coke on the surface of the catalyst and the increase in the yield of aromatic hydrocarbons by the increase in the amount of C2Hy−fragments. According to the conducted experimental studies, the concentration of hydrogen in the gaseous products of the catalytic dehydroaromatization of methane in the vapour phase increases with increasing reaction temperature, and the amount of saturated hydrocarbons and unsaturated hydrocarbons containing double bonds decreases. In the catalytic dehydroaromatization reaction of methane on the catalyst of a Mo-HSZ catalyst in the vapour phase, the conversion rate and the yield of aromatic hydrocarbons increase with increasing temperature and reach 32.3 and 25.2%, respectively, at 750 ℃. For the catalytic aromatization reaction of methane, the acidity centers of the catalyst obtained using ammonium bicarbonate are stronger than the acidity sites of the catalyst prepared by adding hexamethylenediamine. The effect of volume velocity on the reaction rate in the presence of a selected catalyst was studied. [ABSTRACT FROM AUTHOR]

The cracking of heavy oil in the presence of ferrospheres at different duration of the process has been investigated. The use of ferrospheres in the cracking of oil contributes to the intensification of the process of destruction of high molecular weight components of the raw material, the content of which has decreased by almost 14 wt %. The resulting liquid cracking products are dominated by aromatic and saturated hydrocarbons up to 75 wt %. The influence of ferrospheres on the direction of cracking of heavy oil components has been investigated. On the basis of a formalized model of thermal transformation of raw material components, the rate constants of the reactions of thermolysis of bitumen (k) were calculated and the effect of ferrospheres on the ongoing cracking reactions was determined. [ABSTRACT FROM AUTHOR]

The present paper deals with the QSPR analysis of KCD coindices with physical properties of alkanes and monocar-boxylic acids. The correlation study is made between KCD coindices and properties of the same chemical compounds. The result reveals the strong positive correlation for all the properties of alkanes and monocarboxylic acids except for the properties critical pressure(negative) and melting point(weak) of alkanes. [ABSTRACT FROM AUTHOR]

The effect of the Pd and Pt addition into WO3-ZrO2 catalyst on the isomerization reaction of C6-C7 alkanes mixture in the range of LHSV=0.5-4 h−1 is studied. The best reaction performance is achieved on Pd/WO3-ZrO2 catalyst at a temperature of 170°C and LHSV=1 h−1: the yield of heptane isomers is 67.2 wt.% (including DTMS – 26.5 wt.%) at heptane conversion of 86.4%; the yield of hexane isomers is 53.7 wt.% (including DMB – 8.9 wt.%) at hexane conversion of 57.3%. In this case, the RON of the obtained isomerate is 55 points and the yield of stable catalyzate C5+ is 89.8 wt.%. [ABSTRACT FROM AUTHOR]

Biomembran is one type of wound dressing. Wound dressing is usually used in healing wounds and can create good conditions in the process of wound healing. The raw materials used for making these biomembranes are chitosan, alginate, and aloe vera. This study aims to examine biomembrane processing and analyze the physical-chemical properties of biomembrane. The process of making this biomembrane is by mixing all the raw materials, namely chitosan: alginate: aloe vera with a ratio of 40:60:40; 50:50:40; 60:40:40; 70:30:40; and 80:20:40. Then proceed to the stage of printing using glass molds and then dried using an oven. Biomembranes produced were carried out several tests such as for absorption test the value obtained was 73%; 131%; 167%; 258%; and 267% for each of the above comparisons, and for membrane thickness the value obtained is 0.09 mm; 0.0867mm; 0.0833 mm; 0.07mm; 0.0667mm, and for the swelling test the value obtained is 100%; 122.2%; 140%; 200%; 225%, and for analysis of this biomembrane FTIR group contains alkyl halides, CH bonds, alkyl amine groups, NO2 bonds, CO/CH bending groups, NO2 bonds, alkene (C = C), alkaline compounds (C=C), compounds alkanes (CH), and amine compounds, amides (NH). [ABSTRACT FROM AUTHOR]

It is shown that the mechanism of the gas molecules transfer through the lipid bilayer can be connected with the kink-solitons. They are appeared in the lipid bilayer as a result of structural changes in biomembranes. The analytical model describing the behavior of kink-solitons in the finite hydrocarbon chain is presented. The kink-solitons are formed during the folding of the erythrocyte as it moves along the microcapillaries. The equation of the kink-soliton motion is derived. This equation is numerically solved. It is shown that kink-solitons can appear in both saturated and unsaturated alkyl chains. In unsaturated chains, the soliton is "smeared out," CH2−groups vibrate around C=C bonds with a significant amplitude, taking away part of the soliton's energy. The transport of gas molecules by kink-solitons in unsaturated chains is hindered in comparison with saturated hydrocarbon chains. When the mechanical stress field changes, a sharp change in membrane permeability occurs. [ABSTRACT FROM AUTHOR]

The selection of working fluids for Organic Rankine Cycles is an essential part of ORC design, influencing the configuration, the power production and the economic viability. There are several materials with satisfying thermodynamic performances, but due to their environmental impacts, they are ruled out to be used due to international agreements. To have a long life-time ORC-installation, one should find working fluids which have a relatively low impact on Nature and can survive the permanently changing legislative environment. Saturated alkanes are good candidates for this purpose; therefore, a map showing the detailed working fluid classification for a large group of them has been prepared. Separate classes have different properties upon the expansion step of the ORC process. Using this map, one can estimate the applicability of other alkanes (not included to this map) to be used as working fluid. A similar estimate can be done for mixtures of near homologues; in this way, one can prepare practically infinite novel working fluids. [ABSTRACT FROM AUTHOR]

The method of chromatography-mass spectrometry is used to investigate the composition of lipids of ombrotrophic sphagnum peat, which are formed in different natural and climatic zones of Western Siberia. Based on the distribution of n-alkanes and n-alkane-2-ones, the parameters of the reconstruction of peat formation conditions such as temperature, humidity, and plant source are calculated. Taking into account the features of the composition of n-alkanes, a tendency towards a decrease in the index of the average length of the carbon chain (ACL) in the peat of the northern regions of Western Siberia with negative average annual temperatures is revealed. The increase in the KET paleoclimate indicator for n-alkanes-2-ones and the Paq humidity index for n-alkanes is observed in direction from the southern natural and climatic zones to the northern ones. However, the degree of correlation for KET is significantly higher. [ABSTRACT FROM AUTHOR]

The paper presents data on changes in group composition and production rate of heavy crude oil from the Usinsk deposit in the course of successive injections of solutions of surfactants and polymers. It is shown that re-injection of the compositions also results in enhanced oil recovery with involvement of bypassed hydrocarbons and additional production of oil from previously watered reservoirs. Typically, the content of saturated hydrocarbons in the produced oil significantly increases when new areas of deposit are involved into production. [ABSTRACT FROM AUTHOR]

Effect of the fluid type, the conditions of the thermal decomposition (thermolysis) process, and the addition of a zeolite on the degree of kerogen conversion to liquid products have been studied. It is shown that the maximum liquid products yield is achieved during thermal decomposition of kerogen in subcritical benzene in the presence of zeolite. It is established that the use of supercritical benzene as well as supercritical water extraction can increase the oil (concentrate of hydrocarbons) content in thermolysates. The presence of zeolite during the thermolysis of kerogen in each of these media leads to an increase in the content of resins and asphaltenes. The process of thermal destruction of kerogen under supercritical conditions results in an increased content of saturated hydrocarbons (SHC) in oils. Their maximum amount is a result of kerogen thermolysis in supercritical water in the presence of a zeolite. Thermolysis of kerogen in supercritical water with the presence of a zeolite should be considered the most acceptable for obtaining the largest amount of liquid products enriched with hydrocarbons. [ABSTRACT FROM AUTHOR]

The method of selective chemical destruction reveals that the compounds linked to each other or to other structural fragments via ether and sulfide bridges are present in addition to the components in molecular form in the oil of the organic matter of oil shale from the Dmitrievskoye field. It is shown using chromatography-mass spectrometry that "sulfur-bound" and 'ether-bound' saturated and polycycloaromatic hydrocarbons are represented by n-alkanes, hopanes, naphthalenes, biphenyls, phenanthrenes, phenylnaphthalenes, fluorenes, fluorantenes, pyrenes and benzo[c]phenanthrene, perylenes and benzo[e]pyrenes. Unsubstituted structures, namely naphthalene, fluorene, triphenylene, and indeno[1,2,3-cd]fluorantene are only linked through a functional C-S group. The results of the study expand the understanding of the composition of the organic matter of oil shales. They are important for the choice of methods for their processing in order to obtain chemically useful components based on oil shale material, including motor fuels. [ABSTRACT FROM AUTHOR]

Comparative study of Pt-loaded tungstated zirconia and sulfated zirconia catalysts in the isomerization of n-heptane and n-hexane was carried out. According to the FTIR-spectroscopy of adsorbed pyridine, it was found that the Pt/SZ catalyst is characterized by the presence on the surface of stronger Lewis acid sites (a.b. 1448 cm−1) and Brønsted acid sites (a.b. 1543 cm−1) in comparison with the Pt/WZ catalyst (a.b. 1445 and 1538 cm-1, respectively). Moreover, the catalysts are characterized by a different distribution of acid sites: for Pt/SZ, the amount of LAS is five times higher than the number of BAS; for the Pt/WZ catalyst, on the contrary, the number of Brønsted sites exceeds the fraction of LAS by about two times. The difference between the tungstated and sulfated zirconia systems in terms of strength and the number of acid sites explains various regularities of C6-C7 alkane isomerization. [ABSTRACT FROM AUTHOR]

Isomerization of heptane, hexane and their mixture in the presence of Pt/WO3-ZrO2 catalysts was studied. The content of tungsten oxide in the catalysts was varied from 15 to 30 wt.%. It was shown that C6-C7 alkane hydrocarbons are efficiently isomerized in the presence of Pt-containing tungstated zirconia catalysts, both in the case of individual components (heptane and hexane) and their mixture (heptane/hexane=70/30 (wt.%)). Simultaneous isomerization of heptane and hexane over Pt/WO3-ZrO2 catalysts with the tungsten oxide content 15-20 wt.% at 220°C provided the conversion of heptane 91.4-91.5% and hexane 76.6-77.4% at the yield of stable catalyzate 79.3-82.2 wt.%. Therewith, the yields of high-octane dimethyl and trimethyl substituted isomers of heptane (DTMS) and isomers of hexane – dimethylbutanes (DMB) were 25.4-26.9 and 19.7-20.3 wt.% as referred to individual components (heptane and hexane, respectively). [ABSTRACT FROM AUTHOR]

The process of hydrogen sulfide removal from methane with the addition of C6–C8 liquid n-alkanes in a barrier discharge plasma is investigated. It is found out that the formation of high molecular weight polysulfide compounds is due to the lack of a liquid hydrocarbon in the initial mixture, while thiols and alkyl sulfides are formed in a mixture containing an excess of liquid hydrocarbon. The supposed mechanism of transformations is given. A method of process controlling is proposed. [ABSTRACT FROM AUTHOR]

The results of a study of dispersed organic matter (DOM) of the rocks of the lower Cretaceous in the Yamal-Nenets Autonomous Okrug are presented. The molecular composition of DOM and the laws of the distribution of normal and isoprenoid alkanes, phenanthrenes, sterans, hopanes, alicyclic and aromatic hydrocarbons are considered. The data obtained suggest suboxidative conditions that existed in the sedimentation basin, as well as a significant contribution of both phytoplankton and terrestrial vegetation to the original organic matter. The composition of steranes and their reduced amount in relation to that of hopanes suggests the continental genesis of organic matter. [ABSTRACT FROM AUTHOR]

Methane and ethane pyrolysis on the FeCrAl alloy, as a catalyst, in the conditions of its resistive heating is investigated. The cold gas mixture consisting of methane (or ethane) and nitrogen was fed to a spiral heated by an electric current to 900-1300°C. As a result of experiments it is shown that pyrolysis of methane proceeds in two temperature zones with primary formation of ethane and ethylene - in the first and acetylene - in the second. Unlike methane, pyrolysis of ethane proceeds with primary formation of ethylene in the range of 650-950°C. At more high temperatures an exit of by-products of methane and carbon considerably increases. Addition of oxygen both in methane gas mixture and in ethane one, leads to decrease of selectivity of main C2 hydrocarbons due to formation of a by-product CO. [ABSTRACT FROM AUTHOR]

It is well known that soil polluted with different pollutants, including oil, can naturally remediate. Primarily, the process of oil utilization starts with the degradation of saturated alkanes by microorganisms. Alkane monooxygenase is the major enzyme involved in the degradation of alkanes and it is classified into three groups, each catalyzing the degradation of n-alkanes with different chain lengths. In this study, we investigated abundance of alkane monooxygenases genes in the soil contaminated with oil during the process of biorestoration that lasted for 120 days. We conducted a laboratory experiment with three oil doses – 6, 12 and 25% (P6, P12, P25). Dynamics of genes related to group I, group II, and group III alkane monooxygenases were quantified by qPCR. In addition, the total petroleum content and the content of hydrocarbon fractions were analyzed. It was found that the hydrocarbon content did not change significantly during 120 days. However, the content of saturated alkanes decreased by 9.8 and 24% for P6 and P12, respectively. It was determined that I group genes were characterized by a minimal amount in the range from 1.4x10² to 4.4x10³ gene copy number g-1 . The number of genes belonging to the II group was in the range from 2x10² to 7.7x105 gene copy number g-1, and the genes of the III group — from 9.9x104 to 3.2x106 gene copies number g-1 . The content of I group genes increased immediately at the 3rd day after the contamination, and further their quantity decreased in comparison with the uncontaminated soil. The content of genes from the II and III groups increased from the 1st to 3rd days and further continued to grow with the maximum amount at the 30-60 days after the contamination. Thus, it was found that the content of genes encoding alkane monooxygenase increased after oil pollution, while a decrease in the content of aliphatic hydrocarbon fractions was also observed. [ABSTRACT FROM AUTHOR]

The effect of benzene and alcohol-benzene resins extracted from native oil on the structural and mechanical characteristics of a model 6 wt. % solution of oil paraffin in decane was studied. Introduction of alcohol-benzene and benzene resins into the initial 0.3 wt. % solution promotes a decrease in viscosity by a factor of 25 and 125 and pour point temperature by 6 and 14°C, respectively. After alcohol-benzene resins and benzene and resins introduction the cloud point of n-alkanes in solution of oil paraffin solutions decreases from 18.2 to 17.9 and 16.1°C, respectively. [ABSTRACT FROM AUTHOR]