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In the electroplating industry, large volumes of water are used, which are polluted at various stages in the process. Waste water containing transition metal ions is not only a dangerous source of environmental pollution, but also valuable waste. Taking into account the problems associated with the ecology and the rational use of natural resources, it is necessary to create low- and non-waste production, in particular, to develop new technological processes and appropriate equipment, to introduce water-circulation cycles. This paper presents the results of a study of the sorption of copper (II) and nickel (II) cations by the FIBAN X-1 ion exchange fiber. Calorimetric studies of the thermal effects of the interaction of FIBAN X-1 fiber with solutions of copper (II) and nickel (II) nitrates were carried out. It is shown that the power, thermal effect and time of the process depend on the nature and concentration of metal ions in the solution. Based on the experimental data, the enthalpy of the process was calculated. The endothermic effect of the process is explained by the energy costs associated with dehydration effects and changes in the conformation of the polymer fiber chains. Sorption isotherms of these ions were obtained. It has been established that at all concentrations studied, Ni2 + ions under these conditions are absorbed by ion exchange fibers better than Cu2 + cations. The calculated sorption constants for copper (II) and nickel (II) are greater than 1. It is shown that the Langmuir equation describes the sorption isotherm better than the Freundlich equation. For deep purification of waste water from metal ions, it was proposed to use the fibrous sorbent FIBAN X-1.

Currently, the urgent problem is the secondary use of distillation liquid - a waste product from the production of sodium carbonate, which is an aqueous solution containing about 10 % calcium chloride and a small amount of other salts. It is proposed to use a solution based on a distiller liquid as a coolant in a heat exchange system in the production of soda. The introduction of potassium dichromate into the system creates an inhibitory effect and prevents pipe corrosion. To study phase equilibria in the CaCl2 - K2Cr2O7 - H2O system, state diagrams were constructed at temperatures of 20, 3, and -7°C. With decreasing temperature, the homogeneous region noticeably decreases and shifts to the CaCl2 - H2O axis. The eutectic point is limited to a very narrow area in which the weight fraction of potassium dichromate does not exceed 3%.Using the Skrynemakers method, it was found that in a region with a calcium chloride content of less than 40 %, potassium dichromate crystallizes. For the region adjacent to the apex of calcium chloride, it is impossible to establish the composition of the solid phase and the boundaries of its crystallization using the Skrynemakers method. This is due to the fact that the binary system CaCl2 - K2Cr2O7 is a ternary reciprocal system K +, Ca2 + Cl-, Cr2O72- . In this area, the formation of solid solutions or compounds based on the binary system K2Cr2O7 - CaCr2O7 is supposed. For the temperature range from -7 ?С to 50 ?С, the refrigerant composition was proposed: 3 % K2Cr2O7 - 10.2 % CaCl2 - 86.8 % H2O. In the temperature range from 20 ?С to 60 ?С, the composition of the solution is: 6 % K2Cr2O7 – 10 % CaCl2 – 84 % H2O.

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