Rational design of anti-interference Fe/Co MOF-coupled PMS process for As(III) removal in DOM-rich groundwater: 1O2-dominated As(III) oxidation and chemisorption of As(V)

•Fe/Co MOF-coupled PMS for anti-interference As(III) removal in DOM-rich groundwater.•The presence of HA was conducive to enhancing the generations of SO4•−, •OH and 1O2.•Promotion of HA on the regenerations of Fe(II) and Co(II) in Fe/Co MOF-PMS process.•Adsorption processes of As(V) and HA on Fe/Co MOF were fundamentally different.