As3+ removal by Ca-Mn-Fe3O4 with and without H2O2: Effects of calcium oxide in Ca-Mn-Fe3O4

- Ca-Mn-Fe3O4 is manipulated to have a higher Ca wt% with greater surface area.
- An excess Ca wt% in Ca-Mn-Fe3O4 increased the H2O2 reactivity to oxidize As3+.
- As3+ adsorption was reduced with an excess Ca wt% in Ca-Mn-Fe3O4.
- Superoxide anion reduces HMO to Mn2+, and releases Mn2+ into solution.
- Ca-Mn-Fe3O4 itself can oxidize As3+ by H2O2 produced from calcium oxides.