COMPARATIVE STUDY OF METHODS IN THE SYNTHESIS OF MAGNETITE (Fe3O4)

Comparative study of methods in the synthesis of magnetite between hydrolysis oxidative and co-precipitation method has been done. Hydrolysis oxidative method was done by added the solution of KOH (22.45 g) and KNO3 (3.23 g) in water (120 ml) into solution of FeSO4∙7H2O (40.00 g) in water (280 ml) in the N2 atmosphere at 90 oC. Coprecipitation method was done by added dropwise the solution of NH4OH (1 M) into 200 mL of FeSO4 .7H2O and FeCl3 .6H2O solutions (molar ratio 1:2) with total concentration of 6 M until pH 11.5. The solid phase formed in each method was then filtered, washed, and dried. The characterization of product by XRD and FTIR methods indicated that coprecipitation method produced higher in rendemen (81.25%) than that of hydrolisis oksidative method (71.26 %). In addition, the size of magnetite produced by coprecipitation method (15.7 nm) smaller than that of produced by co-precipitation method (27.8 nm)