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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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PURIFICATION OF STARCH-CONTAINING WASTEWATER

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 14-20 p.
Abstract
The paper considers the possibility of purification of starch-containing wastewater by thermally modified waste of sugar production – saturation sediment. Starchy wastewaters with a large amount of organic compounds quickly rot, create a favorable environment for the development of microorganisms, so these waters should be subjected to deep purification. Thermo-modified saturation residue (TMSR) is a fine black powder, the main component of which is CaCO3, formed during the chemical reaction between Ca (OH)2 and CO2 in saturation columns in the process of diffusion beet juicetreatment in sugar production. CaCO3 acts as a basis for the carbon layer, which covers the surface of the particles and formed during the calcination of TMSR through carbonization of organic substances contained in the original saturation sediment. The authors investigated the effect of some technological factors on the purification efficiency. It was established that 40 minutes at a temperature of the reaction medium of 20-30°C is sufficient for flow of the process. The purification efficiency of starchy wastewater systems reaches 88%.
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EXCHANGE OF MERCURY IONS IN INORGANIC ION EXCHANGERS

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 21-31 p.
Abstract
The processes of absorption and desorption of mercury (II) ions on the inorganic ion exchanger “polysurmine” (mixed antimony and silicon oxyhydrate), silicon-phosphorus-antimony ionite, and a composite material based on polysurmine and a polymeric binder are investigated. Experiments were performed under static conditions. High selectivity of polysurmine to mercury ions was shown. The relationship between the structure of ion exchangers and the sorption values achieved is shown, including the influence of a polymer binder that does not have its own ion-exchange capacity on the properties of the composite material. The desorption of absorbed mercury (II) ions from ion exchangers by various desorbents was studied and the efficiency of the latter was compared.
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