Enhanced arsenic removal by in situ formed Fe-Mn binary oxide in the aeration-direct filtration process

► In situ FMBO improved removing As/Fe/Mn in the direct filtration process. ► In situ FMBO accelerated the transformation of soluble As/Mn into the solid phase. ► In situ FMBO enhanced the attachment of particles to the filter media. ► Despite a head loss increase, the cycle run length was not shortened by adding FMBO.