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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 armed conflict between Ukraine and Russia that began in late February 2022 has far-reaching environmental consequences, especially regarding water resources and management. Here we analysed the multifaceted impacts of the military actions on freshwater resources and water infrastructure during the first three months of the conflict. We identified the nature of the impacts, the kind of pressures imposed on the water sector and the negative consequences for the availability and quality of freshwater resources for the civilian population. Our results showed that many water infrastructures such as dams at reservoirs, water supply and treatment systems and subsurface mines have been impacted or are at risk from military actions. Continuation of the conflict will have multiple negative sustainability implications not only in Ukraine but also on a global scale, hampering achievement of clean water and sanitation, conservation and sustainable use of water resources, and energy and food security.

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.

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The main aim of the scientific research was to study the ion-exchange processes in the treatment of industrial wastewaters containing a high concentration of heavy metal ions (Cu 2+ , Zn 2 + , Ni 2+). The sorption results of heavy metal mixtures (Cu-Zn, Cu-Ni) from model solutions of sulfate salts on a strong-acid KU-2-8 cation exchanger in the H +-form were presented. The metals concentration was 10-50 meq/dm 3. The efficiency conditions of cation regeneration in Cu 2+-Zn 2+ , Cu 2+-Ni 2+-forms by 5, 8 and 10 % sulfuric acid solutions were studied. It was shown that the heavy metals from aqueous media can be removed not only from ion exchangers, but can also be restored from regenerative solutions by electrolysis to obtain metals in pure form. In general, the research results showed that the use of ion exchange is very effective in removing the heavy metal ions. The sorption efficiency and regeneration efficiency was about 100%.