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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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PURIFICATION OF OILY EMULSIONS WITH LEAF LITTER OF CHERRY AND ROWAN

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 4-10 p.
Abstract
The paper presents the results of a study of the possibility of using leaf litter of cherries and Rowan, widely grown in Russia, for the extraction of oil of industrial grade I-20A from aqueous media. The sorption properties of cherry leaf litter and Rowan leaf litter were also studied. The bulk density, granulometric composition, humidity, pH of the aqueous extract and losses during the calcination of CLL and RLL were determined. High efficiency of purification of water-oil emulsions is established.
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INVESTIGATION OF WATER ELECTRICAL ACTIVATOR WITH COAXIAL ARRANGEMENT OF ELECTRODES

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 11-18 p.
Abstract
According to the World Health Organization, 80% of diseases are caused by poor quality of drinking water. Therefore, human life, animals, plant growth and development depend on the quality of water. Currently, when there is a continuous increase in the cost of medicines, fertilizers, pesticides, the problem of replacing the above drugs with cheaper substances is relevant. To solve this problem, it is proposed to use electro-activated water and aqueous solutions. On the basis of domestic and foreign experience, leading experts have developed methodological instructions for the widespread use and use of electro-activated water and aqueous solutions in engineering, agriculture, and medicine. For the production of electrochemically activated water and solutions, non-flowing and flow-through modular elements, as well as universal installations, were developed. Currently, a wide variety of electroactivators is offered. Analysis of the structures of these devices showed that flat metal plates are used as electrodes, therefore there are volumes of water that are exposed to uneven electrochemical effects. As a result, the specific energy consumption for obtaining activated water is significant. The purpose of the work is to reduce the specific energy consumption in the production of activated water and aqueous solutions. Coaxial arrangement of the electrodes leads to a reduction in energy consumption. Studies of the electroactivator of water with a coaxial arrangement of electrodes made it possible to establish the optimal ratio between the volumes of anolyte and catholyte and the time of electrolysis of water and an aqueous solution of sodium chloride. The results of the research can be used in the production of electroactivators for personal use as well as in industry and agriculture.
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STUDYING THE PROCESS OF OIL-CONTAINING EMULSION PURIFICATION BY MEANS OF EXPERIMENT PLANNING METHOD

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 19-30 p.
Abstract
The process of oil-containing emulsion purification with chestnut tree waste (CTW) is considered. The factors influencing the process of purification with the application of a full factorial experiment are established. The mathematical model obtained under carrying out a full factorial experiment has the form of a linear equation. The results of the calculation are comparable with the results of the experiment. The data obtained allow conducting a process of water purification at optimal values of technological parameters.
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ON THE CONCEPT OF DEVELOPING OPTIMIZED TECHNOLOGY OF OBTAINING MOLYBDATES AND TUNGSTATES OF d-ELEMENTS IN THE SOLID PHASES ON THE BASIS OF METABOLIC REACTIONS IN THE MUTUAL SYSTEMS MeSO4-Na2CO3-Mo(W)O3 WITH THEIR HEAT TREATMENT ((Me – d-ELEMENT)

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 31-39 p.
Abstract
The paper presents the material devoted to the development of the concept of optimized technology for the production of molybdenum (tungstates) elements of the d-family (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Ag) at a relatively low temperature, based on the model of a physico-chemical system, in which it is possible to form a thermally unstable intermediate phase – donor of high-defect oxide d-element, entering at the time of its formation into chemical interaction with thermally activated Mo(W)O3 with the formation of MeMo(W)O4.
In the process of solving the problem of finding the necessary to achieve the goal of the real prototypes of the chosen model of the physico-chemical system, taking into account the properties of reagents and products of their interaction, and in particular, the thermal instability of carbonates d-elements (their average decomposition temperature 3000C), it was concluded that they can be a system such as MeSO4-Na2CO3-Mo(W)O3, which was justified and confirmed in the laws of physico-chemical analysis, thermodynamics, chemical kinetics, theories of polarization of Nekrasov ions, acids and Lewis's grounds and confirmation in the experiment.
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THE USE OF PEANUT PROCESSING WASTE AS A SORPTION MATERIAL

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 40-49 p.
Abstract
The paper presents the results of the study of the possibility of using peanuts waste processing as a sorption material. The literature data on the use of numerous materials as sorbents are given. Physico-chemical and structural-morphological features of peanut shells were investigated. The object of the study was methylene blue dye as a widely known and used substance, and the sorption capacity for methylene blue is an important characteristic of industrial sorbents. The adsorption capacity of the material is calculated and the adsorption isotherm is constructed. The sorption capacity of the original peanut shell by methylene blue was 0.22 mmol/g.
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DUST WASTE FROM CONCRETE PRODUCTS PLANTS AS AN ALTERNATIVE MATERIAL FOR WASTEWATER TREATMENT

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 50-57 p.
Abstract
The paper presents the results of a study of factors affecting the efficiency of water treatment from heavy metals with dust from bag filters from Belgorod, ZhBI-4. The dynamics of the amount of dust formation of bag filters is given in the paper. The granulometric and phase composition of dust is investigated. A description of the processes occurring when adding dust to the aquatic medium is presented. The effect of dust mass on the pH of the aquatic medium is studied. It was established that this dust can be used as an adsorbent for the waste water treatment from heavy metal ions. High efficiency of wastewater treatment with dust of plant "ZhBI-4" is proved. It is shown that with an increase in the mass of the BFD additive to 0.5 g per 100 dm3, the purification efficiency smoothly rises to 99.9% with the mass of BFD 0.5 g for Sorig = 20 mg / dm3 and 95.3% for Sorig = 10 mg / dm3 The nature of the curve, which reflects the dependence of the PH of the medium on the mass of BFD, is similar to the shape of the curve, which reflects the dependence of the pH of the medium on the mass of the BFD, which emphasizes the effect of the pH of the aqueous medium on the process of formation of Cu (OH)2 precipitate. However, at the same time, it should be noted that the process of treatment from Cu2+ ions also takes place in the range of lower pH values, which exclude the possibility of formation of Cu(OH)2 precipitate. Therefore, treatment can occur due to the adsorption of Cu2 + ions and their hydrolysis products [CuOH] + on the surface of the BFD.
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MAIN FEATURES AND CHARACTERISTICS OF CHEMICAL AND PHYSICAL-CHEMICAL METHODS OF ANALYSIS OF SURFACTANTS

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 4-15 p.
Abstract
One of the most acute and pressing problems of sustainable development in the coming century can be providing the population with quality drinking water. According to estimates of the World Health Organization, the frequency of diseases arising from the use of poor-quality drinking water is the highest. Pollution of the environment by surfactants is a great danger to the entire biosphere. Unlike organic substances, they are not subject to degradation and, in addition to the direct toxic effect on living and plant organisms, tend to accumulate in food chains, which increases their danger to humans.
The flow of surfactants into reservoirs occurs mainly from man-made sources. With the inefficient purification of water, surfactants enter the natural reservoirs, the soil, and along trophic feeding routes reach people. Accumulating in reservoirs, surfactants have a strong toxic effect on the flora and fauna, worsen the organoleptic characteristics of water, prevent the processes of self-purification of water bodies. Even small amounts of surfactants cause abundant foaming, disrupt oxygen exchange in water bodies, and inhibit photosynthesis.
To achieve one hundred percent purification of wastewater from surfactants is almost impossible. In this connection, the search for new and improvement of existing methods of analysis of surface-active substances is very important.
The article presents the main features and characteristics of chemical and physico-chemical methods for the analysis of synthetic surfactants.
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