1982 年 29 巻 7 号 p. 241-245
The aqueous suspensions containing 0.05, 0.10 and 0.20 M Fe(II) with pH 12 were subjected to oxidation with air at 20, 40, 60 and 80°C. The time duration, θe, needed for complete oxidation of Fe(II), which had been detected by the presence of dissolved oxygen in the suspension, was limited between 15 and 180 min by varing the oxidation rate.
Relation between the yield of Fe3O, (X) and θe was obtained as follows; dX/dθe =k(1-X )2 or 1/(1-X)=kθe+1, where k is a function of the oxidation temperature.
The Fe3O4 content of the oxidation product was affected by the oxidation rate and temperature. Settling velocity of the product became faster with increasing X for X≥0.6.