Study On Coagulation Of Catalyzed Iron Internal Electrolysis

The main mechanisms of Catalyzed Iron Internal Electrolysis (CIIE) are the reduction of iron, internal electrolysis of Cu/Fe, flocculation and chemical sedimentation of iron ion. The previous researches on CIIE were about the internal of electrolysis and reduction of iron, but here we took a further research about the coagulation of CIIE.It was feasible to use CIIE as the pretreatment process of municipal wastewater. During the treatment process, most of phosphors and colloid were removed through chemical sedimentation and flocculation of iron ion. Jet aerator and vortex gas pump were separately used as the aerator to enhance the flocculation process of CIIE. COD and the concentration of phosphors were determined to evaluate the effect of the treatment process. With adequate dissolved oxygen and turbulent flow, the CIIE process treated the neutral sewage effectively without acidification. With gas pump aeration, the average removal rate of COD, PO₄^3- and TP were separately 41%, 73% and 60% in the pretreatment process, while the initial amounts of COD, PO₄^3- and TP were 200 mg ? L^-1, 2.0mg ? L^-1 and 2.8 mg ? L^-1, respectively. The problems such as passivation, blockage and agglomeration of filling material were never observed during a long-term running of CIIE.Series of researches were taken on the anion surfactant (LAS) removal by CIIE, such as the removal rate of LAS, the main mechanism and the influencing factors. A mixed system with 100g iron and 10g copper was used to treat 350mL neutral wastewater with 500 mg ? L^-1 LAS. After 90min's treatment of CIIE, the average removal rate of LAS was 78%, and the amount of LAS in effluent was around 100 mg ? L^-1. Further studies on reaction mechanisms indicated that the Cu/Fe internal electrolysis system can't dioxide LAS, and the removal of LAS was the result of the ferric ion's flocculation. In the solution, the iron ion produced by internal electrolysis of Cu/Fe can decrease the cmc of LAS which is not collide itself, and the LAS micelle will come in to being at a lower concentrate. The iron ion can hydrolyze into polyhydric coordination compound which can adsorb the LAS collides, so LAS in the solution can be removed through coagulation process.Some information could be got from the mechanism study: the measures that are favorable for metallic corrosion or those can accelerate the formation of LAS micelle...