No abstract

Analysis of the scientific and technical literature shows that there are quite a few methods of mine water processing. Reagent methods can be considered as the most promising and economically expedient. Mine waters are characterized by a high content of hardness ions and sulfates. The concentration of sulfates varies between 5-35 mg-eq/ dm 3 , hardness -10-40 mg-eq/dm 3 . It has been established that effective purification of water from sulfates can be achieved with the use of lime and 5/6 aluminum hydroxochloride. The efficiency of the process depends on the doses and ratio of reagents. The degree of softening and purification of water from sulfates increases with an increase in the dose of aluminum coagulant within certain limits. When using 5/6 aluminum hydroxochloride, the efficiency of water purification from sulfates is quite high and small amounts of chlorides are introduced into the water with the coagulant.

In this work, the process of water deironing by using magnetite as a catalyst to accelerate the oxidation of iron ions in an aqueous medium was investigated. It was shown that the efficiency of iron ion extraction depends on the solution concentration, sorbent dose and contact time. In all cases, the use of magnetite accelerated the process of extraction of iron by more than an order of magnitude in comparison with similar experiments on the oxidation of iron without the addition of a catalyst. At the pH values greater than 6, the use of magnetite as a catalyst contributes to the deep purification of water from iron ions.

The condition of sources and central water supply systems does not guarantee the required quality of drinking water. A large part of the population of Ukraine uses drinking water that does not meet hygienic requirements according to various indicators. Manganese compounds are quite often present in natural waters. Their quantitative content can vary in a wide range, depending on the region, it can be 5-6 mg/dm3. Manganese in underground waters is presented as ion Mn2+, salts of which are soluble. To remove manganese from water one should transfer it to insoluble state by oxidation. Today, there are a number of typical technologies of demagnetization of water. Many works have also been published which describe the purification of water from manganese ion. It is worth noting that with a high content of manganese compounds in water, their removal is a rather difficult task. Removal of manganese compounds from water can be implemented using the ion exchange method, which consists of filtering water through loading in salt or acidic form. At the same time, softening and desalination of water can occur simultaneously. Therefore, the ion exchange method should be used for comprehensive water purification, softening, and removal of manganese compounds. In order to study the oxidizing capacity of catalytic loading with respect to manganese compounds in water were used as a catalytic load KU-2-8 cationite modified with magnetite and manganese oxide in H+, Na+, and Ca2+ forms. To modify cationite with magnetite under static conditions, it was treated with a solution containing a mixture of Fe2+ and Fe3+ ions in a ratio of 1:2. The research was also carried out on the preparation of catalysts based on cationites by modifying them with manganese compounds. The purpose of this article is to evaluate the efficiency of manganese removal from water when using a catalyst sorbent. The article presents the results of research on water purification from manganese compounds using sorbents-catalysts modified with iron and manganese compounds. It was established that in static and dynamic conditions, complete extraction of manganese ions can be achieved using sorbents based on polymer resin and magnetite. When using cation exchange resin modified with magnetite, the removal of Mn2+ ions from aqueous solutions occurs both due to ion exchange, regardless of the form of the ion exchanger, and due to oxidation on the catalyst (magnetite) in the presence of dissolved oxygen. Modified cation exchange resin in Na+ form leads to the extraction of manganese due to sorption and oxidation of Mn2+. In this case, sorption of calcium and magnesium ions, which is known to be accompanied by an increase in pH. The pH of the medium increased, which increased the efficiency of oxidation of manganese ions on magnetite. Under these conditions, the sorbent catalyst provides complete removal of manganese ions due to catalytic oxidation and sorption of manganese ions on magnetite.

The creation of effective demanganization technologies by the development of new and intensification of known processes of manganese removal from natural waters are currently of increasing importance.The search for promising ways to demanganize water to regulatory values is a topical issue for the modern water treatment domain.Recent publications of methods for extraction of manganese ions from water by sorption, membrane, ion exchange methods were reviewed. The prospects of application of oxidative methods for water demanganation are shown.The purpose of the article is to investigate the manganese ions removal methods from water during their oxidation by sodium hypochlorite and to establish the dependence of the efficiency of demanganization on the consumption of oxidizing agent and the concentration of manganese ions in water.The study presents the application of sodium hypochlorite as an oxidant in the purification of artesian water from manganese ions. It was determined in static conditions that the degree of manganese removal is affected by both its initial concentration in water and the dose of sodium hypochlorite. Water purification process is more efficient with initial manganese concentrations above 5 mg/dm3. At a manganese ion concentration 30 mg/dm3, its complete removal was achieved in 4 hours of settling at a stoichiometric ratio of manganese and sodium hypochlorite in water and at any excess of oxidant. The process of manganese ions oxidation in artesian water by sodium hypochlorite depending on its dose and contact time was studied. The dose of oxidant for the removal of manganese ions from artesian water was also determined. Thus, the research allowed to improve the methods of water purification from manganese ions during their oxidation by sodium hypochlorite and found that the water purification efficiency increased both with increasing consumption of oxidizing agent and increasing the concentration of manganese ions in water.