Abstract:
Birnessite and cryptomelane are typical layered and tunnel manganese oxides and both
can be used as a heterogeneous catalyst for the degradation of organic wastes using
heterogeneous Fenton reaction. This study aims to synthesize these manganese oxides
using KMnO4 (oxidant) and C6H12O6 (reductant) and then doped with Ag+ ion (1%) by
the reflux method of 1 hour and 12 hours. The XRD characterization results obtained
manganese oxides mixed type Ag-birnessite-cryptomelane for reflux time of 1 hour and
Ag-cryptomelane for reflux time of 12 hours. The Ag-cryptomelane (12 hours 1%) has
a surface area of 23.560 m2/g compared to Ag-birnessite-cryptomelane (1 hour 1%)
11.970 m2/g. The manganese oxide that has been synthesized by doping Ag+ ions was
applied for the degradation of methylene blue (MB) using H2O2 as an oxidant. Agbirnessite-
cryptomelane (1 hour 1%) showed a maximum degradation MB result of
75.44% for 120 minutes.
