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Biosorption is a promising technology for removing various pollutants from industrial wastewater, which consists in the use of secondary plant raw materials (e.g., agro-industrial waste) to solve environmental pollution problems. The purpose of this study is to evaluate the potential of nut shells as a biosorbent, to study the effect of alkaline modification of shells on their properties and to study the use of spent biosorbents as additives in cement. The influence of the fractional composition of the initial material on its sorption capacity and the influence of the modification of shells with alkaline solution on the properties of the obtained biosorbents are investigated. The yield of the final products was determined gravimetrically as the ratio of the mass of the product to the mass of the raw material. The sorption capacity was studied using model solutions. The concentration of sodium hydroxide solutions was determined by titration, and the cationic dye by spectrophotometric method. Methylene blue was used as a test dye. The studies have shown that the fractional composition of the material largely determines its sorption properties. Reducing the particle size of the nut shells leads to an increase in the sorption efficiency of methylene blue from 17.2% for the fraction with a size of 1.5-2.0 mm to 39.2% for the fraction with a size of 0.5-1.0 mm. The static exchange capacity increases by an average of 30 % for each subsequent fraction. To improve the sorption properties of the initial material, along with grinding, it is advisable to use chemical modification. The method of alkaline modification was used, which is accompanied by partial destruction of the aromatic component of raw materials and low molecular weight polysaccharides and by removal of extractives of different nature, which leads to the formation of a more porous structure. The maximum sorption efficiency of methylene blue (80 %) corresponds to the biosorbent obtained from nut shells (fractional composition 0.5-1.0 mm) by modifying with 5 % NaOH solution for 180 min at a temperature of 100 oC. Alkaline treatment significantly improves the adsorption capacity of the biosorbent to the cationic dye compared to the initial material. The sorption capacity of nut shells and biosorbent based on shells was studied as a function of pH of aqueous dye solution and duration of contact. It was found that pH of the aqueous solution had a significant effect on the sorption of the dye and the maximum value was reached at pH 6. This is due to the electrokinetic properties of the surface of lignocellulosic materials - the ability to change charge depending on pH (positive in acidic, negative in neutral and alkaline), due to the presence of different functional groups. The study of kinetics showed that the maximum rate of absorption of methylene blue corresponded to the first 30 minutes of contact. Sorption equilibrium is achieved within 240 minutes of contact. Sorption kinetics was also studied using pseudo-first and pseudo-second order models, as well as a diffusion model. The pseudo-second order kinetic model (R2 = 0.99) best describes the absorption kinetics of the cationic dye and suggests that the fixation of methylene blue on the surface of the biosorbent occurs due to various mechanisms. The problem of further use of spent sorption materials is no less important than the efficiency of sorbents in creating an effective integrated water treatment technology. Spent biosorbent was used as an additive to the composition of cement type I/500. The use of plant material in the amount of 5% will not lead to a significant deterioration of the physical and mechanical properties of cement. This indicates the prospects of such an approach in the utilization of spent sorbents. In further research, it is planned to investigate various modification options for plant materials for obtaining highly effective biosorbents of multipurpose function for the solution of environmental problems.

As a result of anthropogenic human activity and the continuous increase in the scale of water consumption, surface and groundwater, which are sources of freshwater, have been degraded. Most water sources have high iron content today. Contamination of groundwater with iron and other metals can occur due to the development of ore deposits and the operation of quarries. Existing technologies only partially solve this problem. Ions of heavy metals are toxic and dangerous for living organisms and for human beings. In this regard, it is important to develop effective methods of water treatment of various pollutants. Today, pollution of water bodies with iron ions has reached a critical level. This creates a problem for many regions not only in Ukraine, but also far beyond its borders. The problem is urgent and needs to be solved. When the pH value in water is less than 6.8–7.0 and the concentration of iron is high, for deep purification, it is advisable to use a combination of a number of methods with the introduction of reagents. Reagent method of deironing is implemented by treating the source water with a suspension of lime water Ca(OH)2. This approach allows one to deirone water effectively, but its implementation is accompanied by the formation of a large amount of sludge, which must be disposed of. An effective way to dispose of such precipitates is their use as a chemical additive in the production of cement, which was confirmed by our research.

Most conventional organic solvents are toxic and pose high risks to human health. In this context, green solvents, such as deep eutectic solvents (DES), are promising and environmentally friendly. DES exhibit the advantages of ionic liquids and, in addition to being inexpensive, are low- or non-toxic, renewable and often biodegradable. The most important by-product generated from the vegetable industry is the so-called pomace that still contains a large number of bioactive compounds of great interest, such as phenolic compounds which have antioxidation properties. Antioxidant compounds are known as molecules that are able to stabilize, inhibit, deactivate and scavenge free radicals, thus protecting the human body against oxidative damage. In this study, a choline chloride-based deep eutectic solvent was used in ultrasound-assisted extraction of "green" organic compounds from tomato pomace (Lycopersicon esculentum. Mill.). Characterization HPLC-DAD methods were employed and total phenolic (TPC) and total flavonoid compounds (TFC) were assayed. Various experimental techniques including DPPH and ABTS radical scavenging activity were used to characterize the antioxidant activity of the extract. The phenolic content of the extracts was determined by the Folin–Ciocalteu method. The results also indicated the highest antioxidant activities measured in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging (40%) and 2,2′-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS)(50%), as well as highest total phenolic content (TPC) (11.12 ± 0.02 mg gallic acid equivalent/g fresh weight). For this reason, in the future, the use of eutectic solvents may be the best method for the extraction of organic compounds from tomato pomace.

The necessity of development of technical solutions that will allow to reduce carbon monoxide emissions of flue gases of industrial productions is substantiated. It is shown that the most rational design solution to the problem of carbon monoxide pollution during the firing of electrode blanks is the use of aerated concrete blocks with a catalyst, which can be quickly and conveniently located directly on the carbon material of the "green" electrodes pouring in the subfloor space of the firing furnaces. Modified by oxides of Mn4+, Fe2+, Fe3+, Cu2+, Cr3+ -catalysts based on aerated concrete were obtained. It is shown that in an empty reactor in the temperature range 200 – 400 ºС the degree of conversion of carbon monoxide in the absence of a catalyst is zero. It is established that on the investigated catalysts based on aerated concrete 100% oxidation of carbon monoxide is achieved at a temperature of 390 ºC in the case of using a mixture of catalyst powders 30 % CuO + 70 % MnO2, 40 % CuO + 60 % MnO2, 50 % Fe (FexCr1-x) 2O4 + 50 % MnO2; 50 % Fe3O4 + 50 % MnO2. It is determined that the addition of ferrite catalyst powder in aerated concrete in a mixture or without manganese dioxide does not critically affect the mechanical properties of the products.

The main direction of the industrial development of Ukraine is the solving of the environmental pollution problems under the conditions of preservation of natural resources through complex use of raw materials with involvement of industrial wastes. The developed technology is intended for galvanic, accumulator, machine-building, mine and other enterprises, the wastewater from which contains ions of heavy metals. Heavy metal ions are extremely dangerous toxic substances because of a cumulative effect on aquatic organisms. In order to remove copper ions from aqueous solutions, the chemical precipitation with lime is used. The choice of reagent is associated with its cheapness. The most effective reagent precipitation of copper ions in the form of hydroxide occurs when the pH is raised to 10. In this work, the influence of sludge, which is formed as a result of water purification from copper ions, on the properties of cement was investigated. The effect was evaluated on the following properties: normal density of cement, hardening time, compressive strength at the age of 2 and 28 days and water separation coefficient. This allowed us to develop effective ways to their disposal. The developed method provides: a high degree of metal removal (up to 98-99%); simplicity of technological process; small capital and operating costs; complex technology of wastewater treatment process. Thus, the results of the study will contribute to the creation of low-waste and non-waste technologies for waste processing and disposal.

Purpose This paper aims to synthesize silver nanoparticles using atmospheric discharge plasma in contact with liquid at different pressure in reactor and to assess their catalytical properties for reducing 4-nanoparticles (NP). Design/methodology/approach The Ag colloidal NPs was rapidly synthesized as a result of non-equilibrium low-temperature plasma formation between an electrode and the surface of AgNO3 solution for 5 min at different pressure in reactor. Synthesized Ag NPs were characterized with common analytical techniques. Ultraviolet–visible (UV) spectroscopy, dynamic light scattering, scanning microcopy analysis were used to study the formation and characteristics of silver nanoparticles. Findings The formation of silver colloidal solutions under plasma discharge at different pressure in reactor is characterized by the presence of surface resonance peak in the spectra. Scanning electron microscope (SEM) images confirmed the formation of spherical particles having a size distribution in the range of 15-26 nm. The AgNPs solution showed excellent rapid catalytic activity for the complete degradation of toxic 4-nitrophenol (4-NPh) into non-toxic 4-aminophenol (4-APh) within 18 min. Research limitations/implications Further studies are necessary for confirmation of the practical application, especially of deposition Ag NPs on TiO2. Practical implications The method provides a simple and practical solution to improving the synthesis of colloidal solutions of Ag NPs for degradation of organic pollutants (4-NPh) in water and wasters water. Originality/value Atmospheric discharge plasma in contact with liquid at different pressure can be used as an effective technique for synthesis of nanomaterials with catalytic properties.

The problem of utilizing plant wastes of the agro-industrial complex is equally important and urgent. In this regard, it is advisable to develop a complex technology of plant waste application to solve the ecological problems of environmental pollution with heavy metals. Modification of walnuts shells with orthophosphoric acid has proven to be a promising process for obtaining the biosorbents with the efficient sorption properties. It was found out that the increase in the concentration of inorganic acid in modification time promotes the improvement in sorption capacity. Such biosorbents can be used in low-waste water demineralization systems. The utilization of waste biosorbents through the use in the composition of building materials is effective from an economic point of view. It was shown that the biosorbent acts as a fine additive; the increase in normal density and acceleration in hardening time takes place. At the same time, the compressive strength of the cement with the application of biosorbents decreases slightly. The results show that the modified walnuts shells have a slightly adverse effect on the hardening time of cement.

The article presents results of the study of the process of electroevolution of copper from regeneration solutions in one- and two-chamber electrolyzers at different concentrations of sulfuric acid and solutions of copper chlorides at different concentrations of hydrochloric acid - in a three-chamber electrolyzer. The conditions of electrochemical recovery of heavy metals from acidic and saline solutions are determined. It is shown that the most effective recovery of heavy metal cations from hydrochloric acid solutions occurs in three-chamber electrolyzers. On the basis of the results obtained, a technological scheme of a local plant for treatment of washing water of galvanic industries is proposed.

The research is related to solving the problem of rational use of materials and to creation of resource-saving technologies for the protection of the environment from pollution by various pollutants. Sorption technologies are quite effective in sewage treatment, but most sorbents are quite expensive, and their regeneration raises the question of recycling of spent solutions. The cheap and availability of raw material base of biosorbents makes these technologies attractive for wastewater treatment. The research is aimed at investigation of ways to effective utilization of spent sorbents, which are obtained after water purification, in the production of building materials. The obtained results allow create a complex low-waste technology of water demineralization and purification from heavy metal ions.

Due to the growth of man-caused pollution, there is a need to use modern methods of water purification. It is advisable to use sorption methods for the extraction of heavy metals, which are considered to be particularly dangerous. It is established that sorbents based on magnetite are quite effective in the extraction of copper ions. It is shown that the sorption capacity of magnetite-based sorbents towards copper ions depends on the ratio of concentrations of Fe2+ and Fe3+ ions in the reaction mixture, and increases with increasing this indicator from 1/2 to 2. The sorption capacity of the sorbent towards copper ions increases by 4.4 times. It is shown that the efficiency of copper ions removal onto magnetite increases for sorbent modified with sodium sulfide. The proposed scheme provides the possibility of sorption treatment of large volumes of water from copper ions to the norms for the discharge of wastewater into fishery reservoirs. Post-productional magnetite is dehydrated and supplied to metallurgical enterprises for processing. The developed technology of water purification from copper ions is environmentally safe and energy efficient.

The issue of desalination is relevant for many countries of the world; the most promising technology for demineralization appears to be membrane technology. The stabilizing treatment of water before feeding it to the membrane filters involved the ion exchange softening of the solution based on the weakly acidic cation exchanger DOWEX MAC-3 in the H+ and Na+ forms. This makes it possible to improve the efficiency of baromembrane desalination and the service time of membranes. The nanofiltration membrane OPMN-P ensures the purification of low mineralized waters from sulfates (by 74–93 %) and hardness ions (67–90 %); at the same time, the membrane has low selectivity in terms of bicarbonate anions and does not retain chlorides. This avoids the accumulation of these in the concentrates at the nanofiltration purification of low mineralized waters. The inverse osmotic membrane Filmtec TW30-1812-50 shows selectivity for sulfates and hardness ions of over 99 %. The selectivity for chlorides is 83–94 % for low mineralized water, and 90–95 % for highly mineralized water. The concentrates contain hardness ions, sulfates, chlorides, and bicarbonate anions in significant concentrations. We have defined conditions for the effective softening of the formed concentrates at the comprehensive treatment by lime and aluminum coagulants. When desalinizing the concentrate of low- and highly mineralized waters, the sulfate concentration decreased to 2.55–6.53 mg-equiv./dm3 and 3.31–9.02 mg-equiv./dm3, respectively. At the same time, the concentration of hardness ions was 3.31–9.02 mg-equiv./dm3 and 4.20–10.65 mg-equiv./dm3. Creating comprehensive technologies for the purification of mineralized waters makes it possible to ensure the proper efficiency of water desalination and to utilize the waste formed with obtaining useful products. That could reduce anthropogenic pressure on the environment and solve the problem of freshwater shortage for people and industry, Проблема опреснения воды актуальна для многих стран мира. Наиболее перспективными для деминерализации можно считать мембранные технологии. Для стабилизационной обработки воды перед подачей на мембранные фильтры использовали ионообменное умягчение раствора на слабокислотном катионите DOWEX MAC-3 в H+ и Na+ форме. Это позволяет повысить эффективность баромембранного обессоливания и срок эксплуатации мембран. Нанофильтрационная мембрана ОПМН-П обеспечивает очистку низкоминерализированной воды от сульфатов (на 74–93 %) и ионов жесткости (на 67–90 %), имеет низкую селективность по гидрокарбонат-анионах и не задерживает при этом мембрана хлориды. Это позволяет избежать накопления данных анионов в концентратах при нанофильтрационной очистке низкоминерализированной воды. Обратноосмотическая мембрана Filmtec TW30-1812-50 имеет селективность по сульфатам и ионам жесткости более 99 %. Селективность по хлоридам составляет 83–94% для низкоминерализированных вод и 90–95 % для высокоминерализованных. Концентраты содержат ионы жесткости, сульфаты, хлориды и гидрокарбонат анионы в значительных концентрациях содержат. Определены условия эффективного умягчения образованных концентратов при комплексной обработке известью и алюминиевыми коагулянтами. При обессоливании концентрата низко- и высокоминерализованных вод концентрация сульфатов снизилась до 2,55–6,53 мг-экв/дм3 и 3,31–9,02 мг-экв/дм3 соответственно. При этом концентрация ионов жесткости составляла 3,31–9,02 мг-экв/дм3 и 4,20–10,65 мг-экв/дм3. Создание комплексных технологий очистки минерализованных вод позволяет обеспечить надлежащую эффективность опреснения воды и переработать образованные отходы с получением полезных продуктов. Это позволит уменьшить антропогенное давление на окружающую среду и решить проблему дефицита пресной воды для населения и промышленности, Проблема опріснення води актуальна для багатьох країн світу. Найбільш перспективними для демінералізації можна вважати мембранні технології. Для стабілізаційної обробки води перед подачею на мембранні фільтри використовували іонообмінне пом’якшення розчину на слабокислотному катіоніті DOWEX MAC-3 в H+ і Na+ формах. Це дозволяє підвищити ефективність баромембранного знесолення та термін експлуатації мембран. Нанофільтраційна мембрана ОПМН-П забезпечує очищення низькомінералізованих вод від сульфатів (на 74–93 %) та іонів жорсткості (67–90 %), при цьому мембрана має низьку селективність по гідрокарбонат-аніонах і не затримує хлориди. Це дозволяє уникнути накопичення даних аніонів в концентратах при нанофільтраційному очищенні низькомінералізованих вод. Зворотньоосмотична мембрана Filmtec TW30-1812-50 має селективність по сульфатам та іонам жорсткості понад 99 %. Селективність по хлоридам становить 83–94 % для низькомінералізованих вод та 90–95 % для високомінералізованих. Концентрати містять іони жорсткості, сульфати, хлориди та гідрокарбонат аніони в значних концентраціях. Визначено умови ефективного пом’якшення утворених концентратів при комплексній обробці вапном та алюмінієвими коагулянтами. При знесоленні концентрату низько- та високомінералізованих вод концентрація сульфатів знизилась до 2,55–6,53 мг-екв/дм3 та 3,31–9,02 мг-екв/дм3 відповідно. При цьому концентрація іонів жорсткості становила 3,31–9,02 мг-екв/дм3 і 4,20–10,65 мг-екв/дм3. Створення комплексних технологій очищення мінералізованих вод дозволяє забезпечити належну ефективність опріснення води та переробити утворені відходи з отриманням корисних продуктів. Це дозволить зменшити антропогенний тиск на навколишнє природне середовище та вирішити проблему дефіциту прісної води для населення та промисловості

Для боротьби з корозією використовують корозійно-стійкі сплави, що вимагає великих затрат і не є достатньо надійним засобом, та інгібітори корозії, які потрібно постійно вдосконалювати для підвищення їх ефективності та зменшення собівартості. Оскільки, корозія характеризується руйнуванням матеріалу внаслідок взаємодії із навколишнім середовищем, то одним із доцільних методів її мінімізації є використання інгібіторів. Тому актуальним завданням охорони навколишнього середовища та економічного розвитку країни є розробка ефективних засобів захисту металів від корозії. Отриманий інгібітор АС-2 (розчин суміші 2-алкілімідазолінів в метанолі) досить ефективно захищає сталь від корозії у водно-нафтових сумішах при високих концентраціях мінеральних солей у воді. Ефективність інгібітору практично не залежить від співвідношення об’ємів нафти та концентрованих водних розчинів хлориду натрію. При використанні інгібітору при концентрації 50 мг/дм^3 ступінь захисту сталі від корозії перевищував 90 %. Пов’язано це з тим, що захист сталі від корозії відбувається за рахунок сорбції імідазолінових складових на поверхні металу та сорбції органічних складових нафти на гідрофобних алкільних групах 2-алкілімідазолінів. При цьому гідрофобізація поверхні металу відбувається в присутності незначних кількостей нафти. Показано, що у суміші, що містила 200 см^3 3 % розчину хлориду натрію та 800 см^3 нафти при концентрації оцтової кислоти відповідно, 0,5 та 3,0 г/дм^3 при температурі 80 ºС при дозі інгібітору 15-50 мг/дм^3 ефективність була 72−92 %. Це дозволяє вирішити проблему раціонального природокористування та забезпечує перехід до використання екологічно безпечних енергоефективних технологій Corrosion elimination implies the application of corrosion-resistant alloys, which is associated with high costs and is not a reliable enough technique, as well as corrosion inhibitors, which need to be constantly improved to improve their efficiency and bring down the cost. As corrosion is characterized by the destruction of a material as a result of interaction with the environment, one of the expedient methods for its minimization is the use of inhibitors. Therefore, it is a relevant task for environmental protection and economic development of the country to devise effective means to protect metals against corrosion. The reported inhibitor AC-2 (the solution of a mixture of 2-alkylimidazolines in methanol) rather effectively protects steel against corrosion in water-oil mixtures at the high concentrations of mineral salts in water. The efficacy of the inhibitor is almost unaffected by the ratio of the volumes of oil and concentrated aqueous solutions of sodium chloride. When using the inhibitor at a concentration of 50 mg/dm^3, the degree of protection of steel against corrosion exceeded 90 %. This is due to the fact that the protection of steel against corrosion occurs through the adsorption of the imidazoline components at the metal surface and the adsorption of organic oil components on the hydrophobic alkyl groups of 2-alkylimidazolines. In this case, the hydrophobization of the metal surface proceeds in the presence of minor quantities of oil. It has been shown that in the mixture that contained 200 cm^3 of a 3 % sodium chloride solution and 800 cm^3 of oil at the concentration of acetic acid, respectively, 0.5 and 3.0 g/dm^3 at a temperature of 80 °C at a dose of the inhibitor of 15–50 mg/dm^3 the efficiency reached 72–92 %. This makes it possible to resolve the issue of the rational use of natural resources and ensures the transition to the application of environmentally safe and energy-efficient technologies.

The paper presents the use of agricultural products, namely grape skins, in the “green” synthesis of monometallic (Au, Ag) and bimetallic (Au-Ag) nanoparticles (NPs) from aqueous solutions of metal ions of the corresponding precursors. At present, there exist urgent problems of utilization of waste from the agro-industrial complex, rational use of nature and transition to the use of environment-friendly and energy-efficient technologies. Therefore, there is a tendency to use “green” technologies in obtaining nanomaterials that are considered environment-friendly and resource-saving. The study has proved the efficiency of using food waste (grape skins) as a reducing and stabilizing agent in forming nanoparticles of precious metals of mono- and bimetallic structures. Biological raw materials were extracted in an aqueous medium under a short-term effect of low-temperature plasma discharges. On the basis of the complex analysis of the extract composition, it was proved that the hydroxyl, carbonyl and carboxyl functional groups of the organic compounds of the grape skin extract are responsible for the recovery of the metal ions and stabilization of the resulting NPs. The research has proved that mono- and bimetallic NPs are formed with the following peaks: for Ag 0 (λ max =440 nm), Au 0 (λ max =540 nm), and Ag-Au (λ max =510 nm). The size and stability of the nanoparticles obtained by the “green” synthesis were assessed in comparison with the same parameters for the plasmochemical method of nanoparticles’ formation. The study has revealed antibacterial, catalytic and anti-corrosion properties of the synthesized nanoparticles. The resulting monometallic (Au, Ag) and bimetallic (Au–Ag) nanoparticles show excellent catalytic activity while recovering p-nitrophenol (4-NPh) to p-aminophenol (4-APh) in the presence of NaBH 4 . The synthesized NPs demonstrate their antibacterial activity against gram-positive and gram-negative bacteria. The findings allow to expand the practical application of metal nanoparticles in various industries and enhance the processing and reuse of non-liquid waste

Розробка ефективних засобів захисту металів від корозії в агресивних середовищах, що містять воду, нафтопродукти, карбонові кислоти та мінеральні солі, є актуальним і практично важливим завданням охорони навколишнього середовища. Для боротьби з корозією використовують інгібітори корозії, які потрібно постійно вдосконалювати та коригувати їх склад. Головним недоліком високоефективних інгібіторів на основі алкілімідазолінів, суміші алкілімідазолінів з алкілпірідінієвими та/або четвертинними амонійними сполуками розчинними в середовищі метанолу є високі ціни при відносно значних їх витратах в корозійне середовище. В роботі синтезовано інгібітори корозії сталі у нафтовмісних водних середовищах, що відповідають підвищеним еколого-економічним вимогам. Показано, що при підвищенні рівня мінералізації води відбувається зростання корозійної активності водних середовищ по відношенню до нелегованої сталі. Наявність вуглекислого газу, сірководню чи карбонових кислот призводять до підкислення водо-нафтових сумішей, внаслідок чого спостерігається підвищення швидкості корозії сталі. Досліджено ефективність синтезованих інгібіторів на основі олії та поліетиленполіамінів, які містять імідазоліни. При температурі 80 °С у суміші, що містила 200 см^3 3 % розчину хлориду натрію, 800 см^3 нафти, концентрації оцтової кислоти 0,5 та 3,0 г/дм^3 при дозі інгібітору 50 мг/дм^3 досягнуто ступеню захисту сталі від корозії на рівні 90–92 %. На основі повного факторного експерименту розраховано рівняння регресії, які дозволяють досить легко розрахувати оптимальну дозу інгібітору корозії сталі у водно-нафтових сумішах. Показано, що синтезований інгібітор перспективний при захисті металів від корозії як в мінералізованих водах, що містять нафту, так і в присутності нафтопродуктів, що містять воду It is a relevant and practically important task for environmental protection to devise effective means to protect metals against corrosion in aggressive media containing water, petroleum products, carbolic acids, and mineral salts. To stop corrosion, corrosion inhibitors are used that must be constantly improved and whose composition must be properly adjusted. The main drawback of the highly effective inhibitors based on alkyl imidazolines, a mixture of alkyl imidazolines with alkyl pyridinium and/or quaternary ammonium compounds soluble in a methanol medium, is their high prices at relatively significant consumption in the corrosive environment. This paper reports the synthesis of steel corrosion inhibitors in oil-containing aqueous environments that meet the stricter ecological and economic requirements. It has been shown that increasing the level of water mineralization improves the corrosive activity of aqueous environments relative to unalloyed steels. The presence of carbon dioxide, hydrogen sulfide, or carboxylic acids leads to the oxidation of water-oil mixtures resulting in the increased rate of steel corrosion. We have studied the effectiveness of the synthesized inhibitors based on oil and polyethylene polyamines containing imidazolines. At a temperature of 80 °C, the mixture that contained 200 cm^3 of a 3 % sodium chloride solution, 800 cm^3 of oil, and at the concentration of acetic acid of 0.5 and 3.0 g/dm^3 at the inhibitor dose of 50 mg/dm^3, has reached the degree of protection of steel against corrosion at the level of 90–92 %. Based on a full factorial experiment, the regression equation has been derived that makes it possible to easily enough calculate an optimal dose of the steel corrosion inhibitor in water-oil mixtures. It has been shown that the synthesized inhibitor shows prospects for protecting metals against corrosion both in the mineralized waters containing oil and in the presence of petroleum products containing water

Development of reliable, environmentally safe and economically advantageous methods of water purification from heavy metals is the primary task for environmental protection. The effectiveness of sorption treatment and additional treatment of natural waters from ions of heavy metals with the use of modified magnetite was studied. The samples of magnetite obtained at the ratio of concentrations of iron (II) and iron (III) of 1:2; 1:1 and 2:1 and the samples modified by sodium sulfide were used as a sorbent. Experimental studies revealed that the sorption capacity of magnetite by ions of heavy metals increases at the increase in the ratio [Fe2+]/[Fe3+] from 1:2 to 2:1. The influence of pH of the medium on the effectiveness of sorption of heavy metal ions on magnetite was studied. It was shown that the sorption capacity of magnetite for ions of copper, zinc, nickel and cadmium increases at the increase in pH of the medium from 6.0 to 8.6 due to partial hydrolysis of heavy metal ions. An increase in sorption capacity of magnetite occurs when it is modified by guanidine, thiosemicarbazide and sodium sulfide, which makes it possible to reduce residual concentrations of heavy metals to μg/dm3. The use of magnetite modified by sodium sulfite, obtained at К=2, makes it possible to completely remove cadmium ions from water and reduce copper concentration to 1.2 μg/dm3. This proves the appropriateness of using these sorbents for additional treatment or deep purification of water from ions of heavy metals. It was shown that it is appropriate to use magnetite for extraction of heavy metal ions from water in the presence of hardness ions, which do not affect the selectivity of this sorbent for ions of heavy metals. Thus, based on the obtained results of sorption purification of water from ions of heavy metals while using magnetite, we proposed a fundamental technological circuit for treatment of wastewater of nuclear power plants at discharge to water bodies

Екстракт жмиху винограду досліджено як новий екологічно безпечний леткий інгібітор атмосферної коро- зії сталі. Протикорозійні властивості оцінено масометричним та електрохімічними методами. Методом ІЧ-спектроскопії та газової хромато-мас-спектрометрії досліджено компонентний складу ізопропанольного екстракту жмиху винограду. Дослід- жено морфологію захисної плівки. Для оцінки адсорбційної здат- ності головних компонентів рослинного екстракту проведені квантово-хімічні розрахунки енергетичних параметрів молекул The inhibition effect of the grape pomace extract during the early stage of steel corrosion under adsorbed thin electrolyte layers was investigated. The present study was carried out to identify the components present in the 2-propanol grape pomace extract by GCMS analysis. Gravimetric, electrochemical impedance spectroscopy, potentiodynamic polarization, scanning electron microscopy, and FTIR techniques were used to study the corrosion inhibitive. Polarization measurements have indicated that these green inhibitors acted through mixed type inhibition. SEM studies have evidenced the formation of a protective film over metal surface while FTIR supported by molecular modelling has proved that this shielding effect was caused by aldehydes particularly 2-phenylacetaldehyde and 3,7-dimethylocta-2,6-dienal.

The results of treatment of solutions with high sulphates concentration and the high rate of water hardness are given. It is shown that significant reduction of secondary pollution by chlorides is achieved through integrated use of aluminium hydroxchloride and sodium aluminate coagulants. It was found that the efficiency of water purification from sulphates and water softening can be increased with the carbon dioxide processing.Представлені результати із очищення розчинів, що містять сульфати у високих концентраціях і характеризуються високою жорсткістю. Показано, що суттєвого зниження вторинного забруднення хлоридами досягнуто при комплексному використанні як коагулянти гідроксохлориду алюмінію і алюмінату натрію. Встановлено, що підвищити ефективність очищення води від сульфатів та її пом’якшення можна при обробленніі води вуглекислим газом.