Abstract:
Cryptomelane-type manganese oxide was successfully synthesized by reflux method
using KMnO4 concentration of 0,25 M with reflux time of 24 hours. The oxide was
then doped with AgNO3 using 1% of ion Ag+ concentration. The Ag-MnO2 material
was prepared via two stages with MnO2 first synthesized , followed by Ag+ doping. The
as-synthesized Ag-MnO2 was then applied as a heterogeneous Fenton catalyst for the
degradation of methylene blue (MB) dye. The XRD results indicated the presence of
mixed phases of birnessite and cryptomelane. The degradation studies revealed that the
activities of pristine MnO2 and Ag-MnO2 for the degradation of MB are similar with the
maximum degradation of 87.72% and 87.79%, respectively using 50 ppm MB ; 5 ml
volume of H2O2 and 0.05 g of catalyst and 120 minutes of reaction times at room
temperature.
