Opposite effects of dissolved oxygen on the removal of As(III) and As(V) by carbonate structural Fe(II).

ABSTRACT: Freshly prepared carbonate structural Fe(II) (CSF) was used to immobilize As(III) and As(V) in wastewater under oxic and anoxic conditions. Dissolved oxygen was found to exert opposite effects on these two arsenic species. The sorption density of As(III) was higher under oxic conditions, whereas that of As(V) was higher under anoxic conditions. X-ray diffraction and infrared spectroscopic analyses indicated that crystalline parasymplesite (Fe(II)₃(AsO₄)₂·8H₂O) was formed when As(V) was removed under anoxic conditions, while an amorphous Fe-As-containing precipitate was formed when As(III) was removed under oxic conditions. The distribution of arsenic and iron between the solution and sediments suggested that the oxidation of structural Fe(II) pro

SUBMITTER: Tian Z 

PROVIDER: S-EPMC5717268 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature