The Niger Delta region of Nigeria is faced with the problem of drinking water supply. Different methods of water purification were compared and reverse osmosis was considered a choice method for the experiment. Among the region's brackish water reserves with heavy metal contamination, nickel and cobalt were considered. Model solutions of nickel and cobalt were prepared to mimic the brackish water contamination levels and were purified with cellulose acetate reverse osmosis membrane. Experimental results showed that purifications were more dependent on the overall salt concentrations and not on individual components.

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The article discusses in detail the membrane processing of complex systems, reverse osmosis (RO) and electrodialysis (ED) membranes. Currently, the development of industrial wastewater treatment technologies is of great interest to many researchers. This is due to the fact that the food, pharmaceutical and chemical industries are becoming increasingly important in our lives, while exacerbating one of the most serious environmental problems, environmental pollution from industrial wastewater, which contains harmful substances in high concentrations. This study is devoted to the analysis of a new technology for the extraction of complex components from industrial wastewater, combining reverse osmosis and electrodialysis. Reverse osmosis systems are pressure controlled membrane separation processes. In contrast, an electrodialysis system is an electrochemical process that is commonly used industrially under normal atmospheric pressure. However, such membrane processes have a significant drawback, the working membranes are contaminated with suspended substances in the wastewater and lose their activity. Therefore, to maintain the activity of the membranes for a long time, it is necessary to pre-treat wastewater by removing suspended solids. The analysis of the recovered components opens up new perspectives for the recovery of industrial wastewater. There is a wide range of methods for pretreatment of water for reverse osmosis and electrodialysis. Ultrafiltration (UF) followed by reverse osmosis is an important process for separating organic and inorganic compounds from wastewater. This article discusses some of these methods. In conclusion, it should be noted that electrodialysis demonstrates remarkable technical advantages in the treatment of concentrated solution after RO.

This work is devoted to study the effect of thermal conditions and concentrations on the diffusion permeability of a cation exchange membrane (MK-40) using sodium chloride (NaCl), sodium acetate (C 2 H 3 NaO 2 ) and acetic acid (CH 3 COOH) solutions, which are usually highly concentrated components of pigment yellow 13 of industrial wastewater. A cell containing two compartments was used to analyze the properties of membrane. The results showed that the maximum diffusion permeability coefficients for NaCl, C 2 H 3 NaO 2 , and CH 3 COOH were 6.08×10 -9 m 2 /s, 13.29×10 -11 m 2 /s, and 25.95×10 -11 m 2 /s, respectively. The increase in the CH 3 COOH solution concentration was found to improve the diffusion permeability. However, the NaCl and C 2 H 3 NaO 2 solutions exhibited decreases in diffusion permeability with solution concentration. There was a significant increase in diffusion permeability with temperature.

The temperature modes of operation of ion-exchange membranes in an electrodialysis apparatus are described. The diffusion permeability of the MK-40 ion-exchange membrane has been experimentally investigated under the conditions of a temperature difference across the membrane at various concentrations of an aqueous solution of sodium chloride. The differences in the diffusion permeability of the membrane in thermostatic and thermodynamic modes are shown. The nature of the influence of the temperature drop across the membrane of aqueous sodium chloride solutions on changes in the value of the diffusion permeability coefficient of the MK-40 membrane was determined.