the stuDy of the pArtIculAr Aspects of wAter purIfIcAtIon froM the heAvy MetAl Ions usInG the MethoD of nAnofIltrAtIon purpose. To develop highly efficient technologies for deep purification of natural water and wastewater from heavy metal com pounds and ions using nanofiltration membranes and complexes to prevent water pollution and protect people and natural objects from the effects of highly toxic pollutants.Methodology. To remove copper ions from the investigated solutions, potassium ferrocyanide was used as a precipitant; the cationic flocculant Zetag7547 was used to improve the sedimentation properties of the obtained solid phase. To extract copper, zinc, cadmium, and nickel ions, HEDP and NTMP complexes were used at a concentration of 10-50 mg/dm 3 . After adding the reagents, the solutions were desalted on a low pressure nanofiltration membrane OPMNP.findings. The optimal conditions for water purification from copper ions by complexation-nanofiltration method were deter mined. A method for efficient extraction of heavy metals from water to acceptable limits using complexones with subsequent nanofiltration desalination was developed.originality. As a result of the conducted research, dependence of productivity of nanofiltration membrane OPMNP on the pressure, selectivity to ions of copper, zinc, cadmium, nickel and on the degree of selection of permiatewas was established. The dependence of the efficiency of pollutant extraction on the type and consumption of complexoneswas was established. It is shown that the hardness ions, hydrocarbons, chlorides, sulfates reduce the selectivity of the nanofiltration membrane to heavy metal ions, so it is proposed to increase the efficiency of the process to prepurify water on the anionite AV178 in the basic form. Potassium ferrocyanide was used as a precipitant to remove copper ions from the test solutions, and a solution of the cationic flocculant Zetag7547 was used to improve the sedimentation properties of the obtained solid phase, followed by purification on a nanofiltra tion membrane, which allowed increasing the degree of extraction of Cu 2+ ions to 99.6 %.practical value. The optimal technological parameters of heavy metal ions extraction from aqueous solutions by means of nanofiltration methods using complexons are substantiated in the work. The developed methods for the extraction of heavy metal ions from aqueous solutions allow reducing their concentrations to normative values. Integrated technologies for water purification from heavy metals make it possible to reduce the mancaused impact on the environment by improving water quality and reducing the amount of waste generated, and to improve the environmental situation in the region.
Національний технічний університет України «Київський політехнічний інститут імені Ігоря Сікорського» ЕЛЕКТРОХІМІЧНА УТИЛІЗАЦІЯ РОЗЧИНІВ ХЛОРИДУ НАТРІЮ З ОТРИМАННЯМ ХЛОРИДІВ ЗАЛІЗА У даній роботі були досліджені процеси електрохімічної переробки розчинів хлориду натрію з отриманням хлориду заліза (III) і лугу в трикамерному електролізері з аніонообмінною мембраною МА-41 і катіонообмінною мембраною МК-40 та в двокамернму електролізері з катіонообмінною мембраною МК-40. Показано, що для підвищення концентрації хлориду заліза (ІІІ) в аноліті при відносно невисоких концентраціях розчину хлориду натрію доцільно в робочій камері поступово змінювати знесолені розчини на вихідні. Доведено, що процес електролізу хлориду натрію в двокамерному електролізері з катіонною мембраною проходить ефективно на початковій стадії процесу за високих значень концентрацій в аноліті катіонів натрію. В подальшому за рахунок отруєння мембрани катіонами заліза процес припиняється.З'ясовано, що при використанні в анодній області залізної стружки, що контактує з анодом, вихід розчинного хлориду заліза не перевищує 15 % через випадання значної кількості оксихлориду заліза в осад при підвищенні рН до 5,1-5,7. Показано, шо підтримання в анодній області трикамерного електролізеру із залізним анодом при електролізі хлориду натрію рН на рівні 1-2 в аноліті дозволяє отримати концентрований розчин FeCl3 при високому виході за струмом як FeCl3 в аноліті, так і NaOH в католіті.
Introduction. The coal mining companies are pumping and discharging into environment the untreated mine-pit and quarry waters that results in a negative impact on natural water reservoirs, and respectively involves a continued reduction in water resources' stocks and quality. The only one mine's untreated water discharge annually produces the environment contamination with more than 26 tons of iron, 1,300 tons of sulphate, 876 tons of chlorides, 175 tons of suspended substances. This problem is particularly acute for the eastern and southern Ukraine regions, where local resources are insufficient to cover the need for quality water. Therefore, the situation implies involving the green technology solutions for mine water treatment problem. Until recently, the most common water treatment technology was ion-exchange one, but it has an important drawback, namely the use of a large reactants' number for regeneration, followed by discharge of mineralized drain water into surface waters. Consequently, this technology application is rational only under condition of effective regeneration techniques development and reduced volume of regeneration solutions used, the third contributive factor being those solutions' subsequent processing. The currently prevailing water treatment technology is reverse osmosis technique, as its application practically excludes the use of reactants, essentially reducing the amount of salt discharged into surface waters; the reverse osmosis is very effective due to high selectivity membranes. But to prevent water resources pollution necessary is to develop solutions for mineral concentrates treatment. Therefore the problem of mine water demineralization and high mineralization index concentrates' treatment is an urgent one. Literature review. The treatment of baromembrane water demineralization concentrates containing only sulphates, hydrocarbons and hardness ions can be reduced to reactant-aided precipitation of sulfate ions and hardness ions in the form of calcium carbonate, magnesium hydroxide and calcium hydroxyl-alumosulphate. However, in the presence of chlorides such demineralization may not be possible because the chlorides in such case shall not be separated of the water. Electrolyzing the solutions containing chlorides and sulphates we can obtain the sulfuric acid and active chlorine [1]. But at that the sulfuric acid contains chlorides (HCl) and active chlorine admixtures. Besides, the active chlorine catching and treatment is a complex process. The concentrates resulting from sulphates' separation at natural and waste water demineralization, can contain apart of hardness ions the sodium cations, chlorides and bicarbonates. The solution containing only chloride anions, carbonates and bicarbonates gives such electrodialysis products as alkali and hydrochloric acid or sodium hypochlorite [2, 3]. In such a way, the separation of chloride and sulfate represents a complex issue and needs to be addressed through new efficient technologies development. Aim of the Research. Investigation of i...
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