The disodium ferrate is very unstable,but its decomposition can be constrained by a strong oxidative agent,sodium hypochlorite.The concentration of disodium ferrate was determined by spectrophotometry directly with pH=12～14 and one percent sodium hypochlorite as a solvent.The accuracy and precision of this method was also discussed in this article.
Several adsorbents such as 4A-molecular sieve,kaoline,zeolite and active white clay are used to stabilize sodium ferrate (Ⅵ) without sodium hypochlorite.It is proved that 4A-molecular sieve,pure kaoline,pure active white clay as well as active white caly prepared by us according to a certain composition can constrain the decomposition of sodium ferrate(Ⅵ).After 30 days,the decomposition percent of sodium ferrate(Ⅵ)adsorbed on these adsorbents is 18.1%,41.7%,3.89%,and 17.5%,respectively.The absorption diagram of desorbed ferrate solution is different from that of pure sodium ferrate solution,and the maxim wavelength is 523.2 nm and 525.2 nm for molecular sivev and active white clay contrasting to 505 nm for zeolite and pure sodium ferrate.
