| 摘要 |
The invention concerns the field water purification, in particular the elimination of heavy metal ions, and can be used for purifying effluent from the electroplating and leather industries, non-ferrous metallurgical enterprises and others. The proposed method of removing heavy metals from water involves the following steps: treatment of the water with a colloidal system containing Fe(OH)3 (0.3-1.3 wt.%), Fe(OH)2 (3.2-6.4 wt.%), alkali metal chloride (0.3-1.0 wt.%), water (the rest); precipitation of the additives and removal of the precipitate, the colloidal system being introduced in a quantity of 1-10 ml for 1 litre of treated water at a pH of 8.0-9.2. The colloidal system constitutes an electro-generated suspension which for the purpose of prolonged storage can be stabilised by the addition of 0.1-1.2 % of a substance chosen from a group including the natural or synthetic aluminosilicates, calcium orthophosphate, as well as inorganic and organic polyelectrolytes. The suspension particles are 5-15 mu m in size, have a specific surface area of 100-250 m<2>/g and the suspension density is 1.05-1.1 g/m<3>. The principle method of producing the colloidal system is by electrochemical dissolution of iron anodes in an aqueous solution with an electrical conductivity of not less than 3 x 10<-3> ohm<-1>cm<-1> with periodic blowing of air until the dissolved trivalent iron content exceeds 10-20 %. |
