Patent ID: 6534032
Filing Date: 2003-03-18
Classification: C01G,C01P,C09C

Abstract:
A process for the production of yellow iron oxide comprisinga) adding an iron component comprising FeSO4 or FeCl2 with an Fe(III) content of 0.5 to 1.5 mol % Fe(III) and a Mn content of up to 0.7 wt. %, based on the Fe content of FeSO4 or FeCl2, to a solution or suspension of an alkaline component that has been heated to a temperature of between 42 and 75Â° C., and b) oxidizing the suspension formed with an oxidizing agent until all iron(II) has been converted into iron(III) as &agr;-FeOOH, wherein the oxidizing agent is added at a rate such that the oxidation time is between 120 and 600 minutes and the reaction temperature during the entire oxidation time is the same as the temperature during step a).