Особенности синтеза ферратов (VI) из сульфата железа (II)

Abstract

High cost of ferrates(VI) - new promising oxidants - stimulates enhancement of Fe(VI) derivatives obtaining technology based on usage of available cheap raw materials. This reaction should be quantitative based on thermodynamic analysis. Nevertheless it was found during carried out experiments that yield of Fe(VI) compounds less than 100%. Influence of operating parameters (hydroxide and hypochlorite concentrations, temperature, molar ratio [ClO˜]/[Fe(II)]) on yield of product has been investigated. It was found out than generation of ferrate decreases with increase of temperature so it is advisable to carry out synthesis in low temperature field (0-5 °C). It is necessary at least twice greater excess of oxidant comparing to stoichiometry to achieve the completeness of the conversion raw material to wanted product. It was found that degree of conversion ferrous salts to ferrates during hypochlorite oxidation increases in row ferrous sulfate - ferrous chloride - ferrous nitrate.