Electropulse treating of humic substance aqueous solutions in a layer of iron granules at water purification

Abstract

The authors have studied the processing of humic substances in a layer of iron pellets with pulsed electric discharge for natural water purification from organic compounds of humic origin in northern regions of Russia, that is relevant for water treatment technologies. The aim of the research is to determine the quantitative characteristics of water purification from humic substances in electric pulse processing in the layer of iron pellets. Methods: photocolorimeter, pH-meter, catalytic oxidation, titrometry. Results. The authors determined the quantitative characteristic of critical micelle concentration in the system sodium humate - iron ions (II), which corresponds to a mole ratio of the components of 2:3. The color of solution and demand of chemical oxygen occur at the specified ratio due to the participation of sodium humate and iron ions (II) in oxidation-reduction reactions with further coagulation and formation of insoluble compounds at pH of 6,5. It is shown that sodium humate increases the efficiency of Fe (II) oxidation in Fe (III). In order to achieve this molar ratio, the action time of pulsed electric discharge was determined experimentally. It is 10 seconds. The paper demonstrates the role of the secondary processes after discharge disconnection. The authors determined the contact time of erosion active products with sodium humate, which is 1 hour. During this time, the values of permanganate oxidation and iron ions concentration in solution achieve the value of maximum permissible concentrations and further increase of the contact time does not result in changing the controlled parameters