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ADSORPTION OF HEAVY METAL IONS BY BENTONITE MODIFIED WITH CARBON NANOTUBES AND ACTIVATED WITH ACID

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 56-66 p.
Abstract
At present, there is no doubt about the need to search for new, more advanced methods and means of treating industrial wastewater. The adsorption method is one of the effective methods for purifying the aquatic environment. One of the sorption materials is bentonite, modified in different ways (by roasting, adding organic components, etc.). Laboratory studies were carried out on the bentonite of the Sarigyukh deposit (Republic of Armenia). The adsorption capacity of bentonite modified with carbon nanotubes with roasting at a temperature of 550°C and subjected to activation with HCl acid was investigated experimentally. It was found that acidic (HCl) activation of bentonite modified with carbon nanotubes and calcined at 550°C promotes an increase in its adsorption activity towards nickel (II) and cadmium (II) ions. The degree of adsorptive extraction of nickel (II) ions after activation of the specified adsorbent with HCl increases by 10%, and the degree of adsorptive extraction of cadmium (II) ions after a similar activation increases by 11%. The characteristics of the efficiency of adsorption of nickel (II) and cadmium (II) ions under static conditions were found with bentonite modified with carbon nanotubes and fired at 550°C, subjected to acid activation with HCl and without it. Bentonite modified with carbon nanotubes, calcined at 550°C and activated with HCl acid showed the greatest adsorption effect with respect to the ions of these metals. Its parameters: in relation to Ni 2+ ions: СОЕ = 852.0 mg-eq/g, Kd = 243.42 mg/dm3, S = 95.4%; to Cd2+ ions: COE = 950 mg-eq/g, Kd = 263.89 mg/dm3, S = 92.0%. The results of laboratory studies made it possible to recommend bentonite modified with carbon nanotubes, fired at 550° C and activated with HCl acid as a sorption material for purifying wastewater from nickel (II) and cadmium (II) ions.
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MINERALOGICAL COMPOSITION OF CLAYS OF THE «POLYANA» FIELD AS POTENTIAL SORPTION-ACTIVE MATERIALS OF INORGANIC ORIGIN

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 67-76 p.
Abstract
This work presents the results of a study of the phase (mineralogical) composition of clay from the Polyana field, Shebekinsky district, Belgorod region. To study the morphological and structural features of the mineral components that make up the specified clay, a set of methods of scanning and transmission microscopy, electron microdiffraction and energy dispersive analysis were used. Electron microscopic examination of Polyanskaya clay showed that it is composed of such minerals as: calcium and magnesium-iron form of montmorillonite, muscovite, low-temperature trigonal quartz, illite and ruthyl. More often than others, the preparations contain particles identified as montmorillonite, differing in structure without shaped edges and having a layered structure (layer thickness of about 1 nm). Particles of this mineral show a high tendency to aggregation, but at the same time they are quite easily split along the cleavage plane during dispersion, and therefore have a developed specific surface area, which determines good sorption characteristics.
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INTENSIFICATION OF THE COAGULATING SUSPENSION EFFECT ON THE EMULSION OF LIPID CONCENTRATE IN WATER

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 77-85 p.
Abstract
The coagulation treatment method is widely used for the effluents of various origins treatment. Substances-coagulants disrupt colloidal formations and contribute to the small particles aggregation, which leads to their precipitation and, as a consequence, a decrease in the organic substances content and the solution turbidity. The most widely used for this purpose are coagulants based on iron and aluminum. The Hermetia illucens insect is increasingly used to obtain chemical raw materials and valuable feed products for the poultry and fish cultivation. Production processes generate effluents contaminated with biodegradable substances, including components of larval fat. In this work, it was studied the coagulation purification possibility of fat-containing effluents from the production of lipid concentrate from the Hermetia illucens fly larvae by a coagulating suspension obtained from the electric arc steel-making furnaces dust, together with a co-coagulant – chestnut leaves carbonized at 400° C, which were used to increase the number of coagulation centers in the system.
The use of a coagulating suspension in the purification of model emulsions gives a low clarification effect (49% with the addition of 0.2 cm3 per 100 cm3 of the emulsion). It was found that the addition of finely dispersed carbon-ized leaves can significantly increase the cleaning efficiency. The best result was obtained by adding the carbonized chestnut leaves in an amount of 0.3 g together with 0.2 cm3 of suspension per 100 cm3 of liquid, while the clarification efficiency of the lipid concentrate model emulsion was 98%, at a pH of 8.
The main stage of coagulation occurs in the first 40 minutes of interaction, after which no changes are observed in the state of the system under study.
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INACTIVATION OF NITROFURAN DERIVATIVES BY FENTON REAGENT

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 86-94 p.
Abstract
The result of human evolution and the development of industry was the emergence of global environmental problems on the planet. Pharmaceuticals is one of the rapidly developing industries and, as a result, a "major supplier of pollutants" to the environment. The search for methods to solve the problems of purification and inactivation of organic toxic pollutants is an important task of modern chemistry. The purpose of this study was to study the inactivation of drugs of the nitrofuran group by hydrogen peroxide in the presence of iron (II) ions.
The study of oxidative degradation of furacilin and furagin preparations by Fenton reagent was carried out. The effect of different concentrations of the oxidative system on the destruction of drugs was compared, optimal conditions for destructive processes were determined. The characteristics of the oxidative degradation of the two drugs are compared, the justification of the differences based on the chemical structure of the active substances is proposed.
The effectiveness of the Fenton system for the destruction of nitrofuran class drugs has been confirmed. Chemi-cal methods of destruction of organic pollutants are advanced and can be used for wastewater treatment of medical and pharmaceutical enterprises, as well as for local treatment facilities.
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PHYTOSTIMULATOR FROM THE WASTE OF CULTIVATION OF THE BLACK SOLDIER FLY

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 95-105 p.
Abstract
The main chemical and sanitary indicators of waste formed during the cultivation of the fly Hermetia illucens were determined. The compliance of chemical and sanitary indicators with the requirements for waste for their use in agriculture is shown. Various methods for preparing a phytostimulator have been tested, the simplest and most effective method has been chosen - with the help of aqueous extraction. Proposed method allows to develop non-waste technology for production of biologically active substances. Based on data on the productivity of the growing process, phenological features of the development of primarily cereal and oilseeds after treatment with a phytostimulator, it can be concluded that it is advisable to use a phytostimulator obtained from Hermetia illucens fly cultivation waste.
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PROSPECTS FOR THE USE OF SOSNOVSKY HOGWEED PROCESSING PRODUCTS IN CHEMICAL TECHNOLOGY

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 7-16 p.
Abstract
It is shown that restrictions on the spread of the invasive and dangerous for humans plant of Sosnovsky hogweed are carried out as needed. One of the restrictions on the spread of this plant can be the processing of Sosnovsky hogweed using chemical technology. It was determined that the optimal conditions from the standpoint of chemical technology are the processing of the fruits of this plant of waxy ripeness. Extraction processing of the fruits of wax ripeness with petroleum ether in a Soxhlet apparatus made it possible to obtain 2.9% of the mass. essential oil, which, according to chromatographic analysis using a gas chromatograph equipped with a flame ionization detector, an electronic integrator Crystallux 4000M, contained 56% of the mass. esters. The work shows that the essential oil in the composition of the compound with vaseline oil in a ratio of 1: 1 by volume can be used not only as a softener in the formulation of rubber compounds based on light crepe, but also as a plasticizer, imparting increased frost resistance to technical rubbers. With practically the same elastic strength characteristics of rubbers under tension with industrial oil I-12A and with essential oil, the increased frost resistance of rubbers with essential oil will allow them to be utilized into crumb rubber for the production of polymer-bitumen binders that reduce cracking of road surfaces.
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STUDY OF AGGREGATIVE STABILITY OF LIPID CONCENTRATE PRODUCTION MODEL WASTE WATER AND POSSIBILITY OF ITS PURIFICATION BY SORPTION METHOD

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 17-28 p.
Abstract
In the Belgorod region, work is underway to create the first high-tech large-scale production of lipid concentrate and animal protein from the larvae of the Black Soldier fly Hermetia illucens in Russia. The lipid concentrate emulsifies well in tap water, which indicates the presence of substances in it that do not belong to triglycerides of fatty acids. Obviously, it contains impurities of compounds present in the larval biomass - protein compounds and their decay products, phospholipids, etc., which can play the role of surfactants. This paper presents the results of studies on the possibility of fat-containing wastewater purification using a sorption material obtained by leaf litter of the horse chestnut genus (Aésculus hippocastanum L.) carbonization. It was found that the lipid concentrate is easily emulsified, both in pure form and in the presence of sodium lauryl sulfate. The resulting emulsions are highly resistant to degradation. It was found that the presence of the surfactant in an amount of 0.01 g/l improves the purification efficiency in the process of the model emulsion adsorption treatment. The addition of 0.6 g of the material allows to reach 92% purification, and with the addition of 1.5 g the efficiency is 98%. Similar amounts of sorbent in a pure emulsion make it possible to achieve values of only 35% and 88%, respectively. When finely dispersed particles of inorganic substances are added to an aqueous medium, the suspension effect is often observed, which manifests itself in the difference between the pH values of the suspension and the filtrate. The results of studies of the amount of added sorbent effect on pH changes in suspensions and filtrates showed that the complex «lipid micelle + sorbent» has a positive charge, and in the presence of the surfactant the charge retains a positive value, but is very close to neutral. An approach to the isoelectric point is observed.
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PALLADIUM NANOELECTROCATALYSTS ON COMBINED MATRIX-SUPPORTS FOR CHEMICAL POWER SOURCES

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 29-36 p.
Abstract
Fuel cells with direct oxidation of formic acid are promising converters of chemical reaction energy into electricity due to the high open-circuit potential, safe (non-flammable and non-toxic) fuel and higher energy characteristics compared to chemical current sources with direct oxidation of alcohols. The crossover effect with a low formic acid content allows the thin membrane application, as well as a high concentration of fuel (up to 20 M), which helps to increase the structure specific power parameters as a whole. Catalysts based on Pt or Pd are widely used in the electrooxidation reaction of formic acid. It has been known that catalysts based Pd are more effective than that Pt due to their resistance to carbon monoxide as the main reaction product. In this paper, the volt-ampere and watt-ampere characteristics of formic acid-based fuel cells and air under model operating conditions were studied. The tests were carried out on a certified laboratory stand of a fuel cell, to which a working model of the investigated membrane-electrode unit was connected. The optimal characteristics of the catalyst loading are established to achieve optimal parameters of current density and specific power. The creation of new catalysts and the modification of existing ones will help to increase the electrodes operation time, reduce the production cost, in-crease their efficiency by increasing efficiency, and also use as fuel not only hydrogen, but also other fuels such as formic acid.
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MODELING OF COMPLEX OF DENDRIMER WITH PEPTIDE

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 37-47 p.
Abstract
Biocompatible branched polymers can be used in many biomedical applications, including drug and gene delivery. In previous articles, we applied a computational approach to study complexes of positively charged lysine branched polymers and their complexes with some negatively charged regulatory oligopeptides. The goal of this article is to test the possibility of complex formation between peptide dendrimer and therapeutic oligopeptide molecules. A system consisting of one dendrimer, 16 oligopeptide molecules and counterions in water was studied by the molecular dynamics method. For this purpose, the Gromacs molecular modeling software package and the Amber force field were used. First of all, the process of complexation was studied and it was shown that negatively charged oligopeptide molecules are attracted by the dendrimer and quickly form a stable complex with it. After reaching a plateau of all characteristics of the complex, its average equilibrium dimensions, shape anisotropy, and internal structure were calculated. They turned out to be similar to the characteristics of the complexes formed by other branched lysine molecules with similar molecular weights and charges.
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SORPTION PROPERTIES OF BLACK SOLDIER FLY (HERMETIA ILLUCENS) MAGGOTS VERMICULTURING ZOOCOMPOST TO «METHYL ORANGE» DYE

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 48-57 p.
Abstract
The paper considers the issues, concerned with possible release as part of sewage waters of an organo-mineral pollutant ‒ methyl orange dye – to the environment. This dye has become widely used in textile industry, food industry, and in building materials production. High concentrations of this dyestuff are toxic and can cause damage to skin and eyes. Getting into the body system, the dye can form even more toxic aromatic amines in course of metabolic processes. The toxic effect can occur even at 5% concentration of the dye.
To reduce the toxic influence of wastewaters, containing dyestuffs such as methyl orange, various purification methods are used, including sorption. To increase the cost-effectiveness of the process, the sorbents, based of various industrial wastes, have found application lately. In the present research the material, based on black soldier fly (Hermetia Illucens) maggots’ vermiculture, was used.
According to experimental findings and the adsorption isotherm, the type of the sorption material’s pores and the type of sorption were determined. It has been demonstrated that the sorption material belongs to transition-porous sorbents, which is essential for extracting large molecules of the dye. According to the isotherm, the dye molecules sorption proceeds in stages: at first, a monolayer is formed, which is indicated by the first plateau in the isotherm. At the second stage, a multilayer in the form of dye molecules’ chains or clusters – the second plateau in the isotherm – is formed. The sorption mechanism is predetermined by the specific composition of zoocompost particles. Zoocompost is rich in humic compounds with such functional groups as ‒NH, ‒OH, ‒C=O. The presence of these groups makes it possible to adsorb anionic dyes, including methyl orange dye, due to electrostatic interactions or hydrogen bonding.
The influence of the sorbent’s weight, particles size, reaction mix temperature, duration of sorption process on methyl orange dye removal degree was studied. The sufficient efficiency of the process up to 90% was demonstrated.
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