PRE-SOFTENING OF WASTEWATER WITH MODIFIED BENTONITE
The electrochemical method of treatment of waste water and liquids waste is compact, effective and is divided into cathodic reduction, electrodialysis and electrocoagulation. At the same time, it should be noted that during the electrochemical reduction of chromium(VI) ions, the current yield of chromium is very low (16-17 %), however, this method can be used to purify waste water from impurities to MPC (maximum permissible concentration). In the process of metal reduction, most of the energy is spent on such undesirable processes as ion polarization, deposition of some impurities in the solution, and the resistance of the electrolyte. In this paper, we conducted research to increase the reduction of hexavalent chromium ions in the presence of polyatomic alcohols such as xylitol, sorbitol, and glycerin. The positive results of them showed a triatomic alcohol - glycerine. The aim of this study is to study the effect of triatomic alcohol on the current yield of chromium in the electrolysis of wastewater with hexavalent chromium ions and determine the optimal conditions of the process. It was found that during the electrolysis of treated wastewater, the use of 1.5-2 % glycerol as an additive to the tested electrolyte under certain conditions increases the current yield of chromium from 18 to 24.5 %.