Catalytic decomposition of hydrogen peroxide in alkaline solutions in the presence of different states of Fe(Ⅲ),free Fe(Ⅲ) in solution and adsorbed Fe(Ⅲ) with cellulose,was studied.The individual and combined roles of DTPA,magnesium sulphate,and sodium silicate as stabilizers for alkaline hydrogen peroxide were also investigated.The most effective way to control decomposition of hydrogen peroxide induced by Fe(Ⅲ) under conventional hydrogen peroxide brightening conditions was examined.The results showed that free Fe(Ⅲ) in solution was present in the form of Fe2O3 crystal structure.Adsorbed Fe(Ⅲ) with cellulose was formed when free Fe(Ⅲ) in solution adsorbed on the surface of cellulose fiber or filled into hollow fiber.Free Fe(Ⅲ) in solutions stabilized hydrogen peroxide,while adsorbed Fe(Ⅲ) with cellulose activated the decomposition of hydrogen peroxide.In the presence of free Fe(Ⅲ) under alkaline condition,DTPA and MgSO4 were effective in reducing the catalytic decomposition of peroxide and the decomposition rates of hydrogen peroxide were decreased to 25% and 50%,respectively.In the presence of adsorbed Fe(Ⅲ) with cellulose,DTPA,magnesium sulphate,and sodium silicate did not have any protective influence to hydrogen peroxide,and the decomposition rate of peroxide was over 80% within 1 h.
