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This article discusses the use of modified molecular sieves in mechanical filters of water treatment plants and the separation of the gas mixture, as they have sorbing properties to all heavy metals. The main indicators of the quality of separation is the adsorption isotherm, which demonstrates the structure of the adsorbent, the thermal effect of separation and a number of other physical,chemical and technological characteristics. System analysis of technological parameters of mechanical filters increases the operational period of equipment.

THE RELEVANCE. Phenols are one of the main pollutants of the aquatic environment and have a harmful effect on the human body. Therefore, their determination today is an urgent problem.   The purpose of this work is to determine the content of phenols in an aqueous medium by gas chromatographic method using various sorption materials.   To do this, it is necessary to consider some features of the gas chromatographic method for monitoring the content of phenols in an aqueous medium using various sorption materials. Based on a detailed literature review to show that phenols and their derivatives are highly toxic substances, have low values of MPC standards, ha\’e a negative impact on the human body, which necessitates their control in the aquatic environment. METHODS. To determine phenols in an aqueous medium, the experimental part of the work was carried out on a Crystallux-4000M gas-liquid chromatograph with a flame ionization detector and nozzle columns filled with various sorbents, as which polyethylene glvcol-1500, SE-30 and arsenated polyethylene glycol PEG(As) were used.   RESULTS. For gas chromatographic separation of phenols and their derivatives, sorption materials of various physicochemical nature were used. It has been established that the most optimal sorbent, which separates almost all phenols and their derivatives, is polyoxyethylene bis arsenate, the molecule of which contains two arsenvl groups capable of intermolecular interactions with the analyzed sorbates.   CONCLUSION. An experimental study of the phenol content in an aqueous medium using a gas-liquid chromatograph Crystallux-4000M was carried out. The characteristics of the retention of phenols on sorption materials  of different physicochemical nature are determined. It is shown that the most complete separation of the individual components of phenol derivatives is carried out on a sorbent prepared on the basis of polyoxyethylene bis arsenate, which is explained by the presence in the structure of its molecule of non-white electron pairs of oxygen atoms capable of intermolecular interactions with the hydroxyl group of phenols. The linear dependence of the logarithm of the relative volume of phenols on their dipole moments and refractive index is established. A deviation from this dependence is obsen’ed for phenols having functional substituents in the ortho-position of the benzene ring. This can be explained by the electronic effect? which leads to steric difficulties during intermolecular interaction in the sorbent - sorbate system. Based on the theoretical studies carried out, it was possible to completely separate the individual components of phenols, especially those with close boiling points. The obtained data were tested in practice when monitoring the content of phenols in the silt drains of the Volga river. This technique of gas chromatographic analysis can be used in the system of ecological monitoring of aquatic ecosystems.

Br, J) получены количественные соотношения между величинами констант квадрупольного взаимодействия e 2 Qq и параметрами J и 3 Э -μ , характеризующими относительную величину пространственного перераспределения валентных электронов ионов 3-Э при варьировании Э и Х. Различие наблюдаемых зависимостей e 2 Qq от дипольных моментов ионов 3 Эμ для молекул в газовой и твердой фазах объясняются влиянием поля кристаллической решетки. Исследованы зависимости значений ЯКР частоты от дипольных моментов ионов 3 Эμ . Ключевые слова: Потенциалы ионизации, электронные пары, дипольные моменты, константы квадрупольных взаимодействий, электроны валентной оболочки иона Э -3 , ЯКР частоты.

THE PURPOSE. In order to control the technical condition of oil-filled electrical equipment, a number of new analytical methods have recently been created to determine the ultra-low concentrations of impurity compounds in transformer oil. An analysis of the literature data showed that at this stage of the analytical procedure significant errors may occur that worsen the quality of control of the technical condition of oil-filled electrical equipment, and in some cases make its results meaningless. The published literature practically does not discuss the problem of sample preparation of transformer oil, which negatively affects the quality of analytical control, that is, the reliability of the results and, accordingly, the diagnosis of oil-filled electrical equipment. METHODS. The paper discusses a sample preparation system for transformer oil, which is based on various methods for extracting target components from it. The adsorption process is used, the preparation of chemical derivatives, various types of extraction, liquid, gas, solid phase and fluid, as well as using low temperatures, extraction in microwave, magnetic, electromagnetic and centrifugal fields. It is shown that liquid extraction with an organic solvent is widely used from all sample preparation methods, with the help of which furan compounds resulting from the destruction of paper insulation are extracted from transformer oil. The disadvantages of sample preparation using liquid-phase extraction and the possibility of using solid-phase extraction on various adsorbents for this purpose are discussed. RESULTS. The results of an experimental study of the sorption properties of various organic solvents with respect to porous materials differing in the structure of their surface are presented. We used zeolite-bearing rocks of the Tatar-Shatrashansky deposit, synthetic zeolites NaX-13A. Using the ascending variant of liquid column chromatography, the absolute retention values of standard extractants were determined and their dependence on the length of the sorption layer of the porous material was found. CONCLUSIONS. It was shown that the highest retention times for all studied adsorbents are observed for organochlorine extractants, chloroform, carbon tetrachloride, dichloroethane, trichlorethylene. For N. Hexane is a relatively small interaction. Histograms are given of the effect of the retention time of standard sorbates (extractants) on their physicochemical nature.