Research On Preparation Of Potassium Ferrate(VI) And Its Properties In Decolorization Of The Azo Dyes Wastewater

Potassium ferrate (K2FeO4) is considered as an non-chlorine highly-efficient environmental friendly multi-functional water treatment agent.It has novel properties of oxidation, flocculation, coagulation, adsorption, deodorization, disinfection.it has not been studied extensively owing to difculties with its instability in water and its risk. Unstable performance of potassium ferrate in neutral and acidic conditions, rapidly decomposed, and the highly oxidized (in acidic and alkaline solution, power of Fe (Ⅵ)/Fe (Ⅲ) in the standard electrode potentials were to 2.20 V,0.72 V), Compared with chlorine water treatment agent, K2FeO4 products to rust, which is floccular and no harmful effects on the people and the environment,not cause secondary pollution. It is truly a green inorganic water treatment.Therefore K2FeO4 is ideally water treatment agent.At present, the preparation of K2FeO4 is still remain in the laboratory study, not a good product available.owing to harsh operating conditions, low producting recovery rate, poor stability, complicated preparation. This paper from the preparation methods, analysis methods and applications described three aspects to present.The iron source usually used in preparing potassium ferrate is iron chlorate, iron sulfate, iron nitrate and so on. In this paper we prepared K2FeO4 through oxidation of KClO and Fe(NO3)2·9H2O.Studied the preparation of ferrate oxidation reaction time, the sand core funnel model and the number of its purification yield. Also compared with arsenate, chromate titration of Asia has been improved.And hydrogen peroxide were prepared ferrate were studied, the choice of raw materials of iron, alkali concentration and the dosage of EDTA and other factors the system.In this paper, potassium ferrate was used to degrade active Brilliant Red X-3B(monoazo dye), Crocein scarlet MOO(disazo dye), Direct Fast Scarlet 4BS(disazo dye), Direct Black 19(tetrazo dye). We use the structure change reflected by UV spectrum to evaluate the disposal effect of azo-dyes by potassium ferrate and the decoloration of azo-dye. We systemically studied the decoloration affected by the technical condition of this method which are pH of the initial solution, the supply of ferrate, the time of oxidation reaction, the initial concentration of dyes, the temperature of the reaction.The main factors are the pH of the initial solution and the supply of ferrate.