The studies were conducted on the natural waters of Georgia: Gortubani and Naminauri (Adigeni region), Danisparauli, Dandalo and Makhinjauri (Adjara region) which exhibit medicinal properties. The following water indicators were determined: titratable acidity, electrical conductivity, hardness, the content of solids, sulfates, chlorides, hydrocarbonates, nitrates, ammonium salts and metals. These indicators were determined in the source water, as well as in the concentrate and permeate obtained by ultrafiltration. The productivity of the ultrafiltration process was determined, its dependence on the duration of the process, the applied pressure and the location of the spring. The productivity of the Danisparauli water ultrafiltration process decreases with time; the productivity remains unchanged during the filtration of the Makhinjauri and Naminauri waters; during ultrafiltration, the titratable acidity of the Makhinjauri water increases significantly, by 66.5%, that of the water Naminauri by 36.6%, the titratable acidity of the Danisparauli water remains unchanged, the sulfide ion content in the Makhinjauri water increases by 12%, and in the Naminauri water by 35.5%, the chloride content in the process of concentrating practically does not change. It was found that all the investigated waters are contaminated with heavy metals and the population should not use them for treatment. The data obtained can be used to simulate the purification of natural sources.

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The process of non-reagent adjustment of the pH of a NaCl solution (0.5 g/L) of different acidity was investigated by the method of bipolar electrodialysis on a device operating according to the K-system (concentration). The experiments were carried out in the range pH = 2.0–12.0 with monopolar cation-exchange MK-40 (for alkaline solutions) or anion-exchange MA-40 (for acidic solutions) and bipolar MB-2 membranes. The regularities of the change in the pH of the solution on the current density, process productivity and energy consumption for the neutralization process have been investigated. Revealed: with different productivity of the apparatus (Q = 0.5–1.5 m3/h), in the range of pH 3.0–11.0, with an increase in the current density, a neutral pH value is achieved. It has been shown that at pH above 11.0 and below 3.0, even at high current densities (i > 20 A/m2), its value cannot be changed. This is due to the neutralization of the H+ or OH− ions generated by the bipolar membrane by water ions, which are formed as a result of the dissociation of water molecules at the border of the monopolar membrane and the solution under conditions when the value of current exceeds the limiting value.

The widespread use of surfactants increasingly requires the development and application of reliable methods for the demineralization of wastewaters, preventing environmental pollution. One of the most reliable and effective methods of demineralization of wastewaters is the electrodialysis method. Studying the behavior of large organic ions in the membrane is important for modeling cell membranes and purification of medicinal and biological preparations. The sorption characteristics of the MA-40 and MK-40 ion-exchange membranes in solutions of simple and organic electrolytes, and in a solution of the surfactant were investigated. It was found that the sorption of organic ions by membranes is mainly of an ion-exchange nature. The moisture content and elasticity of the membranes decreases in solutions of organic electrolytes, during the sorption of which the membrane becomes brittle. A study showed that in the solutions of organic electrolytes, the MA-40 membrane retains high electrochemical activity, while the MK-40 in a solution of the surfactant completely loses it. From the data obtained in this work, it is shown that organic ions do not present а hazard when water is desalted by electrodialysis, whereas sorption of surfactant ions leads to membrane poisoning.

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