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2019

Archives Journal Chemical Bulletin Vol. 2

INVESTIGATION OF TECHNOLOGY FOR EXTRACTION OF HEAVY HYDROCARBONS FROM ASSOCIATED PETROLEUM GAS BY LOW-TEMPERATURE SEPARATION

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 4-11 p.
Abstract
The article is devoted to the description of studies aimed at studying the process of separation of associated petroleum gas into fractions by the method of low-temperature separation. The work uses Aspen Hysys software, which allows to model technological schemes containing various types of equipment, solve problems by selected numerical mathematical methods and thus to study the progress of practically any physical and chemical processes. Consideration of this problem is a pressing task, as it aims to save and improve the quality of valuable hydrocarbon materials. At the same time, the influence of various factors on the process of separation of heavy hydrocarbons has not been studied yet and there is no developed and simple method of monitoring the state and composition of oil and gas products at different stages of processing. To demonstrate the developed method, the composition of the initial mixture is specified and a simplified computer model of the process of extracting heavy hydrocarbons is created. The influence of one of the main factors acting in this process, temperature, on methane yield and heavy hydrocarbon fractions was investigated. Based on the results of the work, recommendations for improvement of this technological process are proposed. The methodology and results of the carried out studies can be used for further study of processes of associated petroleum gas processing, including using more complex technological schemes. This technique can also be useful for research of processes of processing of any hydrocarbon raw materials (for example, oil of different deposits), as well as other commercial chemical products.
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SULFURIC ACID MODIFIED SAWDUST OF ACACIA AURICULARIS (ACACIA AURICULIFORMIS) FOR THE PURIFICATION OF WASTEWATER FROM COPPER IONS (II)

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 12-23 p.
Abstract
Modified sorption materials based on acacia sawdust (Acacia Auriculiformis) were obtained by treating their surface with low-concentration sulfuric acid solutions with concentrations of 1%, 2% and 3%. According to IR spectra, diffractograms, micrographs and histograms of the distribution of surface roughness of native and sulfuric acid-modified acacia sawdust, it was found that surface treatment of the sawdust with acid solutions leads to a change in the structure of the sorption material, namely, leaching of low molecular weight components from the composition of acacia wood. The regularities of the processes of adsorption of Cu2+ ions by native and sulfuric acid modified acacia filings under static conditions were studied. Using the obtained values of the initial and equi-librium concentrations of copper (II) ions in solutions, the sorption capacities of the materials were calculated and the adsorption isotherms of Cu2+ ions were constructed using native and modified acacia filings. Processing acacia sawdust with sulfuric acid solutions leads to an increase in the sorption capacity for copper ions, while the greatest sorption capacity is observed in the case of acacia sawdust treated with a 3% sulfuric acid solution. By processing the obtained sorption isotherms in the framework of the monomolecular models of Langmuir, Freindlich, Dubinin-Radushkevich, Temkin, the regression equations and approximation coefficients are determined. It was revealed that the processes of adsorption of Cu2+ ions by native and modified acacia sawdust with a 3% sulfuric acid solu-tion are best described by the Langmuir model, and the processes of copper ion adsorption by acacia sawdust mod-ified by 1% and 2% sulfuric acid solutions are described by the Freindlich model. The thermodynamic constants of the adsorption processes are calculated, from the values of which it is determined that all the studied processes belong to the processes of physical adsorption. By processing the kinetic dependences of the processes within the framework of the diffusion adsorption model, we calculated the Bio coefficients for the sorption processes of Cu2+ ions by native and modified acacia filings, the values of which determined the limiting stages of the processes (mixed diffusion).
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OPTIMIZATION OF RECTIFICATION PROCESS DURING BUTANE PRODUCTION

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 24-31 p.
Abstract
The article describes the method of studying the parameters of the rectification process in the production of butane from associated petroleum gas. The method allows to optimize this process in terms of reduction of energy and operating costs and to achieve the goal of increasing efficiency of separation of hydrocarbon components of raw materials – mixture of gases. These tasks are relevant, as their solution saves expensive energy and valuable commodity products. However, mathematical modeling of rectification processes is very complex and problematic without the application of modern numerical methods and computer programs solving systems of hundreds of nonlinear equations. One of the most suitable programs for such modeling is Aspen Hysys, which also allows to create visual diagrams of technological processes used in the oil and gas industry. This paper considers one of the problems solved in butane production – reduction of operating costs by reducing power consumption when selecting the number of plates of the rectification column and the number of the feed plate to which the initial product is supplied. The composition of the gas mixture is taken for one of the oil and gas deposits, which is char-acterized by a high proportion of butane in the associated gas composition. Aspen Hysys has developed a process model for producing butane that meets product requirements. Based on the results of the work, recommendations are given on the application of the developed methodology for the study of the influence of various factors on the efficiency and cost of technological processes in which rectification columns are used.
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COMPARISON OF SORPTION PROPERTIES OF NATIVE AND HEAT-TREATED PEANUT PEEL AGAINST NICKEL IONS

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 4-9 p.
Abstract
The paper presents the results of investigating the possibility of increasing the sorption capacity of peanut peel after heat treatment at 300°C for 30 minutes. World peanut production is about 40 million tons for 2017-2018. The peel remaining after peanut processing is not used and it is unused waste. For research peanuts were taken growing in the valley of Aleppo (Syria). It was established that after heat treatment, the peanut peel surface becomes more prominent, which improves its sorption properties. During the heat treatment, the charring of the plant fibers that make up the peel occurs, as a result of which the surface of the material is covered with a layer of soot and becomes black. The black color has the greatest intensity during heat treatment at 300 oC. At lower roasting temperatures, the carbonization of the fibers is insufficient.At higher temperatures, the carbon layer is burning with the formation of CO2.
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SYNTHESIS OF METAL-CONTAINING IONIC LIQUIDS FOR CLEANING PETROLEUM PRODUCTS

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 10-18 p.
Abstract
Imidazolium zinc-containing ionic liquids (IL), [1-R-3-R'-imidazolium] alkyl sulfate-ZnCl2 (R and R '= H or alkyl), were very effective for removing nitrogen from a model fuel containing quinoline, indole, or acridine in n-heptane. The interaction of EtSO 4 and ZnCl 2 (EtSO 4) with a heterocyclic N compound was studied theoretically. Zn-containing IL, [EMIm] ZnCl 2 (EtSO 4) used to recover quinoline were successfully regenerated using diethyl ether as the back extractant.
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ORIGINAL CATALYTIC SYNTHESIS OF MACRODIOLIDES CONTAINING 1Z, 5Z-DIENE FRAGMENT AND THE STUDY OF ITS ANTITUMOR ACTIVITY IN VITRO

 19-25 p.
Abstract
An original strategy was developed for the synthesis of valuable unsaturated macrocyclic lactones, macrodiolides, containing a 1Z,5Z-diene moiety in 57-79% yields and >98% stereoselectivity by hafnium triflate Hf(OTf)4-catalyzed intermolecular esterification of aliphatic α,ω-dicarboxylic acids with α,ω-alka-nZ,(n+4)Z-dienediols (1,12-dodeca-4Z,8Z-dienediol, 1,14-tetradeca-5Z,9Z-dienediol, 1,18-octadeca-7Z,11Z-dienediol). The diols were obtained by homo-cyclomagnesiation of tetrahydropyran ethers of oxygenated 1,2-dienes with EtMgBr in the presence of Mg metal and Cp2TiCl2 catalyst (10 mol. %). The resulting macrodiolides exhibit high cytotoxic activity in vitro against Jurkat, K562, U937, Hek293 and HeLa tumor cell lines.
The problem of stereoselective methods for the synthesis of macrocyclic compounds containing 1Z, 5Z-diene grouping in their structure was analyzed, using 1,2-dienes (Cemilev reaction) using alkyl halide derivatives of Mg (RMgX) by Ti- action at a key stage of the synthesis, containing complex catalysts. The resulting macro-carbocycles are of interest as new synthetic biologically active precursors for the creation of modern drugs for the treatment of cancer.
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THE ELEMENT WITH CONSTANT PHASE SHIFT IN GALVANODYNAMIC MODE

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 4-8 p.
Abstract
The purpose of this study is to study the behavior of the boundary perfectly polarized electrode – solid electrolyte in the presence of a constant phase shift impedance (CPS) in the galvanic-dynamic mode.
Analytical expressions of the dependence of the potential of the interface of an ideally polarizable electrode-solid electrolyte on time in the galvanodynamic mode in 2 cases are obtained: 1) in the case of a full equivalent electrical circuit; 2) in the case of a reduced equivalent electrical circuit. The complete coincidence of analytical expressions for the potential of the interphase boundary in both cases is shown.
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HEAVY METALS IN THE ENVIRONMENT AND THEIR TRANSFORMATION

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 9-14 p.
Abstract
The information about the presence of heavy metals in the environment was summarized. It is noted that most of them are extremely toxic, even in residues. According to the basis from various literary sources, data are presented on the properties of heavy metals to influence physical and chemical and biological interfacial interactions. It is shown that soil minerals play an important role in accelerating the abiotic processes of polymerization and polycondensation of organic compounds. At the same time, oxides of aluminum, iron and manganese are the most reactive catalysts for the conversion of many organic compounds due to their high oxidation potentials, high specific surface area and surface reactivity. Heavy metals can enter the body during breathing. When entering it heavy metals can cause various health damage including cancer, liver and kidney diseases, abortions, neurological and visual damage, a negative effect on the immune system, allergies, cardiovascular diseases and anemia. An important way for heavy metals to enter the body is through drinking water. The third way is through food with a high content of heavy metals. It is obvious that there is the urgent need to reduce the mass of heavy metals entering the environment, in water bodies with sewage in particular.
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DETERMINATION OF MERCURY IN WINE SAMPLES USING OF SILICA, MODIFIED BY POLYHEXAMETHYLENUGANIDINE

 15-20 p.
Abstract
The aim of the work was the development of a sorption-atomic-absorption method for determining mercury after its separation from wine samples in the form of a complex with unithiol on modified polyhexamethylene guanidine silica. The sorption-atomic absorption determination of mercury in wines was performed using the cold-steam method. The developed method is characterized by a low detection limit and a sufficiently high accuracy and satisfactory reproducibility.
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FRUMKIN-MELIK-GAYKAZAN MODEL IN THE CHRONOPOTENTIOMETRIC AND CHRONOAMPEROMETRIC MODES

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 4-13 p.
Abstract
This study analyzes the behavior of a metal electrode in an organic electrolyte containing a surfactant with the property of adsorption in chronoamperometric and chronopotentiometric modes.
Analytical expressions of dependence of potential of interfacial boundary metal electrode-solution of indifferent organic electrolyte on time; and also analytical relation of dependence of current passing through a cell on time in chronoamperometric mode are received.
Graphoanalytic method established that the dependence of the potential of the interface metal electrode-solution indifferent electrolyte, which has the property of adsorption on the electrode, in the Frumkin-Melik-Gaykazyan model in chronopotentiometric mode is exponential. The dependence of the current through the cell on time in chronoamperometric mode is also exponential.
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